you are nicer than me

Your suggestion should be the first step.  But he needs to collect evidence ASAP because the phone record will be difficult to get if more than a year.  The longer to wait, the more difficult to find records and support documents.

one reason I think hoa did bad is the late notice.  They should send notice earlier, not one year later.  And they should not send attorney letter without a regular notice.  It is not normal.  Either they send a wrong letter or use the deadline as a trap.  That is reason for unfairness of the deadline.