Intermittent Starter problem: opinions please


He has a 2000 MN6 coupe that is having intermittent starter failure.
Turns the key, gauges sweep, everything is powered up, fuel pump runs, but the starter doesn't do a thing.
He can bump start it.
The ignition switch has been replaced before.
It may be coincidence, but he says this began happening only after he had a dealership perform the column lock recall work (don't know how long ago that was done).
Doing a search, some similar posts have suggested...
New ignition switch
New battery
Clutch disengage switch
TDR relay - whatever that is
and of course, checking what codes may be present.
Anybody had the same symptoms and what was your fix???
Thanks




