Cant get third Crest after defeating Chronozon

[Roblorobot92]

I would like some assistance in getting the third crest piece that you get from chronozon in the Family Crest quest, i had a full inventory when i tried picking it up and am now stuck since he wont respawn and i tped out not noticing it wasnt picked up, i have screenshots if needed

What i did was i killed him, tried to pick up the crest piece while having a full inventory, then tped out without realizing it
after this, the quest log says i killed him and picked up the crest piece, but since my inventory was full the second part did not happen
now Chronozon wont respawn and i cant complete the quest since the crest piece despawned