Retirement tax questions

1. You are correct, the description should be 2020 Excess 401k Deferrals.
2. I received back the excess contribution in 2021, should it still be 2020 Other income?: See 2020 Publication 525: Taxable and Nontaxable Income, page 10 and 11. Yes, it should still be in 2020 Other income.
3. No, report the full amount of the distribution. You will capture the loss in 2021.
4. It depends. If it was not issued, it cannot be included. The excess deferral is added to your wages in 2020. 

@orangelena