This is where you start: "A client had two accounts with a brokerage firm."

"Account" is too vague.

It seems your taxpayer had a Retirement account and an Investment account.

"she took all of the money"

What does "took" mean, specifically? I would have her speak with that investment broker who accepted the funds, who should have done some due diligence and would discover the Regular funds (the $16k) were not allowed to be put into an IRA. Everyone in that field knows there is an Annual Limit. This partial amount from the old Investment account should have triggered some questions. And the excess (whatever she doesn't qualify for) needs to be removed, so she needs to talk to them anyway.