How did the excess deferral come about? If only one employer was involved, the plan should have rejected any attempt to make an excess deferral.
My first thought was that you could treat the distribution from the 401(k) as having included an amount that was ineligible for rollover and that you could obtain a return of excess contribution from the traditional IRA. However, after reading Opus 17' s reply, I think my first thought was wrong. An excess deferral did not create and amount that was ineligible for rollover and, with no money in the 401(k) now, you are simply unable to request a return of that excess deferral.
The only potential way I can think of to avoid double taxation would be to roll some amount back into the 401(k) to be able to obtain the corrective distribution, but, even if that's possible, I think that that would be fraught with danger. If the amount of the excess deferral is small, I think I would just include the excess in income on your 2023 tax return and be done with it. Yes, it will eventually get taxed again when distributed from the traditional IRA, but if the excess deferral is small, that would be the safe thing to do.
