I'm not a tax person, so you'll need to wait to see if anyone comments here in that regard about any tax aspect. They may also need more info, such as if it was "your" account, a deceased relative's account and you're the executor or beneficiary, etc.
I'm going to ask @dmertz who is someone familiar with retirement plans if they have anything to say about this situation.
Addendum:
Was this unclaimed property that you received through the Texas Unclaimed Property website; i.e., from the State Comptroller? Such as listings at https://claimittexas.org/
As far as any reporting by the State of Texas, this is one of the FAQs at the Claim It Texas website:
"Will you issue an IRS 1099 form?
No. If you have concerns about tax reporting, consult a tax preparation expert."
Source: https://claimittexas.org/app/faq-payment
