The iODBC and OpenLink ODBC traces you provided are for the iODBC Administrator64 app which they clearly state, and not for Excel.
Also, why are you using the iODBC Administrator64 (Intel x64) app on an M1 machine, as I would expect you to be using the iODBC Administrator universal binary (M1 & Intel64) app enabling it to work with application build with either chip as detailed in the OpenLink ODBC Driver and iODBC usage on Apple Silicon M1 machines post ?
Is your Excel application a universal (M1 & Intel64) or M1 only or Intel64 only app ?
As you cannot connect with iODBC Demo to PostgreSQL 15.x , we would like to see the ODBC (iODBC and OpenLink) traces for such connection/query attempts, as requested previously.