Well I got termed as an L4 and have to pay back 5k any advice?

Long story short my L6 was termed and while ERC investigated my entire team I think I either self-reported or got collaterally fired with my boss and 1 other person on the team. I was on military duty when they called to ask questions and persisted I answer and speak to them. So I did and was kind of in a rush answering questions ( didn't know I was being investigated at all) sounded like it was all about my boss. I got pulled in randomly told I was getting termed for policy violation and asked what policy. They said they didn't know I had to contact ERC since it came from them.

I contacted ERC and they said its handled at their level and I can't do an appeal through them and that someone from my FCs HR was supposed to contact me to do an appeal. No one has in over a week and I just received a payback notice of 5k. I work for a "right to work state" so they can technically fire me for whatever reason. I'm just pissed about paying for this bonus after they just did me like that. I'm not sure if I should contact an attorney or what about paying this back. I don't have 5k after getting terminated to just pay back in less than 30 days. Would love any advice.. I really liked my job and have to find a way to let my parents know that I got fired after 4 months.