All
From what I have gathered with the latest details from your reports, the bug with the new plant is that when it tries to teleport the target, it can crash your game with the following conditions:
1) zombie which has be transformed into a plant (which is on your side and fight for you)
this would be from Witch Hazel
2) zombie which has been hypnotised (which is also on your side and fight for you)
this would be from Caulipower, Enchant-mint and Hypno-shroom
3) zombie which has been swallowed or eaten whole by your plant
this would be from Shadow peashooter, Grimrose, Conceal-mint, Chomper, Snap Pea etc)
4) zombie being zapped by two Hocus crocus at the same time (I think this is very rare as I have been using two pre-planted ones in matches and they seems to be ok even though I feel being cheated as sometimes the zapping is on the zombies' favour, for instance, the zombie was saved from being exploded by my potato mine)
5) zombie being blown up by mines
this would be primal potato mine or high level potato mine
I will add more to the list when there is/are new ones being reported.
Edit: mistypes