Retirement tax questions

Thank you, dmertz. Very helpful and appreciate your detailed explanation. All valid points and confirms my understanding as well.

 

So I should expect two 1090-Rs? One with a Code E now in 2022 for the failed conversion and the other one in 2023 with Codes J and P? 

 

My understanding is that I need to file an extension 1040x and write  pursuant to "301.9100–2". This per IRS guidance apply to elections for which corrective action is taken on or after December 31. I have looked it up and it seems right. Any thoughts on this?