My Final Week's Pay Was "lost In The Mail" Is This Still A Violation Of Wage Laws? (ma, Us)

I live and work in Massachusetts, USA. One of our labor laws says that if you are involuntarily terminated from your job you must be paid your final wages THAT DAY for hours you've worked that pay period. Even if they pay you the next day, it's still violating the law. An employer could face fines from the state, be required to pay the employee twice what they're owed, and if it needs to go to court they will have to pay all legal fees. At least this is how I understand it after reading the actual laws and the summaries on the official state website.

2 weeks ago I was fired for violating a policy. I was told by the manager that he would make sure I got paid "as soon as possible" and I agreed to leave quietly and not make a fuss. 2 weeks later I still haven't gotten my money. I assumed they were direct depositing it on the normal payday, but that came and went. I got a paystub in the mail yesterday saying that my pay was put on a "PayCard", but I had never been given any cards and I checked for any unopened junk mail and found nothing.

I just got off the phone with my manager and he said that after I left he loaded a PayCard with my final earnings and sent it to me in the mail. Like I said, I'm 100% sure I never received it.

So my question is, did he violate the law but not giving me my pay at the time? I know he must have had the time to do it because he had enough time to arrange for another manager from somewhere else to be in the room as a witness. Even if he did mail it the day that I was fired I wouldn't have received it until 2-4 days later. He'll be able to provide proof that the card was loaded that day, but I never signed anything acknowledging that I had received any money that day.