God, I really feel for Isidro throughout this entire mission. He's already treated like a joke as is, and in a situation like his where he's in the company of a living legend, a master swordsman rivalling that legend, and the former head of the church's inquisition, god knows my pride would be shot to hell and back. I totally get him being so desperate to be 'superior' to someone else. And when the new party member shows herself as an apprentice, and one smaller than he is, it must be absolutely humiliating to get ragdolled the way he's been.
I really hope Isidro manages to keep pace with the rest of the gang, and doesn't just devolve into an overconfident comic relief character. He and Puck are a great comedic duo together, but I'll be super disappointed if that's all he really ends up amounting to.