402(g) excess--employee contributed to multiple plans

I feel like I should know the answer to this one but I don't.  We sponsor a 403(b) and one of our participants deferred the maximum to both our plan and his former employer's 401(k) plan in 2022.  (Yes, 2022.)  He is now (December 2023) requesting a refund from us.  Can we do it?  He is active and under 59 1/2 and we do not consider him to otherwise have had a distributable event.  If this were a 401(k) I would say "no" but I am unsure about the 403(b) aspect.

https://www.irs.gov/retirement-plans/consequences-to-a-participant-who-makes-excess-annual-salary-deferrals

Generally I would say it's too late for the refund.  We had a similar situation, but the participant contacted the plan in October 2023 for a refund of excess from 2022.  This participant was located in California, and the IRS had extended various due dates due to natural disasters earlier in the year (including California).  Based on that guidance the plan felt comfortable to process the refund at that time.