This is the update from 2010 from Rogean regarding pet changes to exp on p99. AFAIK it was the last time that they tinkered with the code for this, but I could be wrong.
https://www.project1999.com/forums/s...highlight=pets
Rogean: Pets doing 50% of the damage to a mob will now take 50% of xp If ungrouped.
Testing should settle it, but my understanding was that 1) total pet damage can only steal the exp if you are ungrouped and 2) only if you are ungrouped and the pet does 50% of the total damage.
I may have misread your data initially, it does some to hold up.
Did you happen to test what would happen if you did 1 damage while grped and both in exp range?
I've wondered what happens on my enchanter how it would work if I charm, fight, break charm, recharm and then kill. Is the total damage washed away with the new charm? Never tested it, but always wondered myself.