How Do Mashups Work?

Hello people, I am a fairly new EDM producer and I need some advice.

I recently made a mashup of two tracks. Both of these tracks are remixes of more popular songs that have gone viral.

I took a small part of one of the tracks and added it to the other track. I used AI stem separation on the other track I completely changed the arrangement of it and also added my own sounds.

Now the problem is when I asked one of the producers (who is pretty big compared to me) if he is okay with me releasing this, he told me that he is not. I am wondering how much power does he have over this. His track is pretty much a remix of another popular track, so it’s not like he isn’t infringing some copyright laws also.

Other then that I do not plan on making any money from this. I just want to release it because it sounds good and it took me a lot of time to make it.