I have his 2019 return and broker A 1099 statement. He did $6k backdoor , broker A generated a 1099 with $6k into IRA and immediately into Roth. So 2019 looks fine, no other IRA balances.

For 2020 I receive 2 x 1099's. Both say for 2020 tax year - so can this refer to a 2019 contribution? I don't believe so. 

Sequence is:

in May 2020 he contributes $6k post tax into traditional IRA, immediately backdoors into Roth. I had no idea till received 1099 today. Broker A generates a 1099, looks the same as 2019 above, but says 2020 tax year. 

Then comes to my firm for tax and investments. Rolls Roth money to my company.  In Dec 2020 he says lets do $6k back door.

I open IRA, fund  it post tax, back door it immediately into the Roth he moved over to me.

He has no other IRA balances. So no aggregation or basis issues that I can see.

Today I get a 1099 from broker A and one from my firm each showing $6k into IRA and then into the Roth's a day later.

My concern is that both 1099's go to IRS and I have to show $12k on his 1040, and code it in IRA works as non-taxable.

From what I read I need to reverse the $6k from the Roth as a corrective distribution. This will, however, only generate the 1099 distribution form in early 2021. I am not sure how/where to enter into Intuit the corrective distribution so that the IRS does not start the clock on the 6% penalty for excess contribution. 

Not really following how 5498's drive the contributions as that's money in. If i have 2x 1099's showing $12k into IRA's - is that not a problem for the IRS?

Thanks again