Same thing as if he were diagnosed with long Covid (or cancer, or COPD) in October and doesn't expect to have income for the next 15 years.  The interest rate is low and I think the FTP penalty runs out after 50 months, doesn't it?  File the return and maybe there will be a pardon.  Otherwise, I have had more than one client get an unexpected check for more than $100,000 from a long-lost relative who had money but no Will.