Estate Final Return - Distribute Remaining Cash

Descendant's IRA lump sum distribution went directly to their estate/EIN on a 1099-R, with withholdings taken out. Estate filed 1041, reported the income and received a small refund (because of the withholdings). No other estate expenses or income, no probate. Tiny estate and should have been handled differently. Do we need to file a final 1041 return now checking the "final return" box? How do we report the distribution of the already-taxed cash? Is that corpus now? 1041 Schedule B line 10 Other Amounts to be distributed? Would there be K-1s in this case of no expenses or taxable income to be passed? Thanks