How Do I Prove My Asshole Neighbor Killed My Cat. And Or Take Revenge Without Getting In Trouble (too Much)

keep in mind i live in norway so the laws here r alittle diffrent than most of u, tho ik theres alot of norwegians on reddit.

when i was 4 we got a cat that for the sake of the story and to keep annonymus we will call him Giovanni as his name is the name of a famous opra so ofc his fake name has to be one too.
Giovanni is a 16 year old purebred siamese with show and breeding line papers. in other words, his worth more than the avrage blue collar workers paycheks.. we got him when he was 2 years old. he was instantly locked on me like a lovely little fussy parasite and was for his entire life.
almost 1 year ago we moved into the forest, 2 neighbors on either side about 200 meters from both. middle of nowhere. the neighbors hated us instantly for zero reason, they claimed we wer speeding (we wer going 30 in a 70 zone..) and that we wer waking everyone (the house is quiet after 8)and so much more lies, they wer so phsycotic and annoying that its just exhausting to think of them.

but 5 days ago it was 7 months since me and my family, mom and my siblings went on a 1 day trip to sweden for some shopping and a cabbin stay with a waterpark and stuff. 1 dey vecation, while we wer packing the car i asume Giovanni got outside (indoors cat) as he likes to sit outside with me on the pattio or bite the grass while i take a smoke. so i assume he was siting somewhere on the front of the house when we left.

to keep in mind for the next part i will tell u a bit about how Giovanni is, his VERY particular with how he wants things. for first he is a large cat, his bulky and muscular compared to other siamese cats, his a LARGE male. yes we live in the forest but there dosent exist a fox that could kill him, his vicous if he wants to be or its someone he dosent like. but the sweetest and most naive to strangers and family. he hates other animals in general, will rummble and ignore them unless they come up twards him. has launched himself at several medium and small dogs. in other words, wildlife would not have gotten him. this is important to the story. another very important thing to the story probebly one of the most crusial. Giovanni HATES, and i mean HATES to get dirty, especialy on his paws. he would NEVER walk off the road and into the grass or dirt, he would only hord to the pattio, diveway and road. he has been left outside for a few days before when we used to live in the city and nothing has ever happened any of the times, one time he killed a giant hare that was in the driveway one of the times.

so with that said, when we got back from the roadtrip the durring the early night the next day, Giovanni was NOWHERE. and giovanni like all siamese, r super vocal, he will allways answer to his name or just any sound u make to a cat. he was nowhere in the house, we even emptied all clossets and storage to see if he got stuck somewhere. we went outside and looked but didnt tell the neighbors as tho it was early night it was too late to knock at the neighbors doors. we couldnt find him anywhere. cat tracks in the road but nothing else. i was out in the woods and local barns looking for him the entire night.

but now going to the accual juicy and legal part

done with the backstory as its mostlikely boring to u most, but very crusial to understand how i come to this conclusion on what has happened.
the day after, we got a call from the landlord saying "i herd ur cat is missing, no need to think more about that. it is how it is" in a weird way, think kinda like a suspicous but authoritory way not leaving u to rlly say anythign against it. but the problem here is the landlord dosent live anywhere close to this part of norway even. and we didnt tell the neighbors the cat was missing. so that means the neighbors has told the landlord (one of the annoying neighbors was calling the landlord for stupid things all the time) that our cat is gone. wich she could not have known.
this leads me to think she had directly something to do with his dissepearence.
i dont know how she made the landlord shut about it but most likely did so to buy herself some time but she fucked up. after our cat went missing she stoped bothering us for quite a while before starting up again even worse. i think she went int oit even stronger after this beacuse she thinks she can get away with "getting rid" of my Giovanni.
the neighbors kept telling us "the cat was old and probebly went into the forest to die, too fall asleep peacefully" wich is utter bull.. a siamese cats life expectancy is far higher than a normal house cat. being at 20-25 years old, sometimes longer. oldest cat in the world, a 34 year old siamese.and Giovanni was in no way in an ageing state even, the week before he was fighting a hairbrush and throwing his food pellets around my floor.

i belive they have either hit my cat with their truck, ATV or shot him (suprisingly its not uncommon to shoot cats in norway, tho it is VERY illegal)
in this case they would likely have burried the cat on their property so it cant be found in the woods or side of the road or smt.

what i want legal advice on is this.
i intend to hire a Cadaver Dog to find him. the soil around this city and county is very wet and humid, so the body would not have decomposed to bones yett. so if the dog finds the cat his easily deffinable, and if it has decomposed alot, his still chipped.
a cadaver dog can smell a cadaver within minutes of death all to 25 years later, so even tho its 7 months ago its more than doable.

i need to know if i legaly can bring a cadaver dog into their property. if i can i will, if i cant i'll do it when their out.
i also need to know wich things i can take her for if i find my cat.
what i got down is:
- animal cruelty
- Emotional damage/disstress
- replacement of the cat (having to pay back the value of the animal)

as just finding my cat will bring me peace, but she desserves to be charged with anything she can be.