sorry, but this strategy absolutely sucks. completely passing doesn't work bc then by the time the 3rd pet comes in, the red spore is dead, so you can't explode. you need to keep healing your first pet instead of passing. If you change that, your strategy would work way better. Especially with how RNG heavy it is for your first 2 pets to die. (edited)
This strat is fine but it completely misses the point. You don't need any specific pets. Just high level ones that will survive 11 rounds in total. You won't get much XP but you can have any pet with Explode as your 2nd pet and let the 3rd pet get a couple hundred XP in the end.