hmm...
A few points.
Radarvectors and "cleared to IAF". I understand this clearance as own navigation to the fix, but minimum vectoring altitude applies. This would be in a circumstance where MSA was higher than 3000'.
If you are cleared ILS, you are cleared to do everything depicted on the approach chart. That means (subject to various local regulations) arriving within 30degrees of final approach course, you intercept and join the localizer.
The holding in question, is it really a holding? My guess would be a race-track alignment procedure, that you are required to perform when arriving outside 30 degrees of FAC.
On the Jeppesen chart... Is the holding depicted as a thin or a bold line?
Happy easteregg hunting!!