Resolved in an hour!
I removed myself as AU from DH's Amex card, after realizing it affected my Age of Accounts.
Amex quickly reported the account closed on Transunion and Experian. I don't see the account on Equifax. I was hoping Amex would remove the trade-line from my reports but maybe they only have the ability to close it.
Yesterday after I saw the account was closed I opened disputes with Transunion and Experian, letting them know this DH's account and I'm not responsible for it.
Transunion emailed me within an hour, showing a resolution. I logged in and the trade line was gone.
Very quick service from Transunion.
Edit: changed "deadline" to trade-line.
