I'm a bit confused. $100,000 of net profit from self-employment is plenty to allow a $16,000 SEP contribution. $87,000 of net profit would be enough.
Assuming that you did make a $2,000 excess SEP contribution in 2023 and no longer have any money in the SEP-IRA, I think I would consider that $2,000 to have been distributed as a return of contribution (with no adjustment for earnings needed since this happened immediately after the contribution), $14,000 properly rolled over to the 401(k) and a $2,000 excess contribution to the 401(k) that still needs to be corrected. On your 2022 tax return you would show only a $14,000 SEP contribution. In 2023 TurboTax you might enter a substitute code-G 2023 Form 1099-R with $14,000 in box 1 instead of $16,000, then enter a substitute code 8 2023 Form 1099-R with $2,000 in box 1 and zero in box 2a. Both of these Forms 1099-R must have the IRA/SEP/SIMPLE box marked. The explanation for each of these would indicating that the $16,000 distribution included $2,000 of excess contribution that had no adjustment for earnings because the $16,000 distribution occurred immediately after the excess contribution was made. However, entering substitute Forms 1099-R will likely force you to print and mail your tax return. An alternative would be to report the code-G 2023 Form 1099-R as received since the result on Form 1040 would be the same ($16,000 on line 4a, $0 on line 4b), then just provide explanation to the IRS if they ever question the transaction.
The corrective distribution for the excess $2,000 401(k) contribution needs to happen by April 15, 2024.
