When Maws Jr comes in, why would you keep using Falcosaur Swarm! until dead? That would take several more rounds than it needs to! If you use Ironskin as soon as it comes off CD, you only need one more Falcosaur Swarm! before you can use Predatory Strike to win the fight; i didn't even need my third pet.
Because the enemy moves are RNG once you get to enemy pet 2 & 3, I can't guarantee people will be able to do more than Falsocaur Swarm once the last pet comes in. People are more than welcome to do more, but the Swarm until Dead will be more useful, more often than not, than trying to add moves for people to complain; "But mine didn't get more than a swarm, so this strat is terrible."
Because, believe me, I've had comments for this exact situation before, so I go with what I know will work the majority over the lucky RNG scenario where you can 2-pet this.