If her 2020 return was processed then the address was probably updated for the 2019 amended return so it probably will go to her however she cannot legally negotiate the check without your signature so the advice to use your attorney to "encourage" her to do the right thing would be the way to go. As for if the check was released yet try to get that info by signing into your IRS account online here :
https://www.irs.gov/payments/view-your-tax-account
Even if you are a spouse on the amended return it is still your return as well and you should be able to get information on that return. Did you try the WHERE'S MY AMENDED RETURN? tool yet ... you must use her SS# to access that portal : https://www.irs.gov/filing/wheres-my-amended-return
