Ex forged my signature on tax ?

my estranged husband splits his time between northern california and taiwan, few months here few months there... 6 months ago he forged my signature on our tax return... I let it go and didn't do anything. I recently found out that he is in taiwan at the moment and received our stimulus check, he had his mother forge both our signatures and deposit it into his account... his sole account not a joint account. I already contacted IRS and they said theres nothing they can do and that I need to contact local police. I have already contacted the sheriffs and they are looking into it. What can I expect to happen. I hate to see anything bad happen to his mother but I'm tired of being taken advantage of and forging my signature is NOT ok.

If you don't get any satisfaction from the sheriff dept,contact your local District Attorney. The IRS is a government agency,they both could be looking at some federal charges. They are both guilty in this. Don't feel bad for his mother,I'm sure she knew what she was doing was wrong. In fact,she is more guilty than he is. She has no legal ties to you at all and had no right to forge your signature.