"simply taking money out of his Roth"

You don't seem to also have a conversion. Conversion is pre-taxed value moved into a nontaxable account, and that Conversion is taxable, to not lose track of the fact that the money was never before taxed and won't be taxed in the future (when taken out). So, the IRS taxes it at the time of the move.

"Since the "conversion" was totally Roth related, I considered it a non taxable event."

A distribution from a Roth is subject to ordering rules. And there are various 5-year tests, for tax and penalty.

https://www.investopedia.com/terms/o/orderingrules.asp

https://www.investopedia.com/retirement/tax-treatment-roth-ira-distributions/

You should only need the Form 5498 (an information form) for contributions and for valuation.

Where is his 1099-R? You use that form for income tax prep.