If you signed the tech log your PIC you signed for it.
Personally if I go over the 90 days I just go and do 3 circuits on my tod.
The reason why its so foggy is because everyone wants to log PIC. The instructors want it because they think its one step nearer flying an airliner. Punters want it for the 12 hours or if they are hour building for the PIC time for CPL.
So everyone wants to play with the definitions so they can log something other than dual. The CAA has written the rules and they are perfectly clear its just human nature means people want to interprate them to thier own advantage. Personally if I was the instructor with you I wouldn't log anything, but then again I have have over 4k hours and day job is LHS in a multi crew aircraft and another hour in a SEP added to the 1200 I have already is neither here nor there. But to an instructor who is sub 1k hours ever hour is golden