"-- If the money is withdrawn before the tax deadline, then I can avoid double taxation. In that case the over-contributed money would need to be taxed as 2022 W2 income, and the early withdrawal penalty would be avoided."
That statement is somewhat incorrect. With regard to correcting an excess deferral, the statutory deadline was April 15, not the deadline for filing your tax return, so it's too late to obtain a return of the contribution. You must now include the excess contribution in income (because it was excluded from the amount in box 1 of your Forms W-2) and it will simply be taxed again when eventually distributed as a regular distribution. Enter the excess deferral into TurboTax under Wages& Income -> Less Common Income -> Miscellaneous income, 1099-A, 1099-C -> Other income not already reported on a Form W-2 or Form 1099, answer Yes to receiving other wages, proceed until you can answer Yes to earning other wages, select Other as the source of the other earned income, then enter the excess deferral. TurboTax will include this on Form 1040 line 1h.
