Didn't expect that, great idea. Though what he said before this is still valid, but if he knew this all along then I'm glad that the mc really does not stand with miracles like in every other story and valuates his real chances, I'm guessing if he wouldn't actually have this stored power of his, he really would have tried to escape, which is completely reasonable, "Live to save another day", his 2 friends may die, but if he doesn't die, he potentially could save many others, especially if he gets stronger.
Other than that, he would be right about not having to care about anyone else, but his friend, after all it is completely tjis other world's fault that they are now in all of this mess, and his friend. No one can look down on him for not caring about anything, but himself and his loved one, especially that from the start they were the ones who made the two of them suffer and go through all of this, expecting that he should care even little bit about anyone else is hypocritical.
But this is all just a fictional story, I'm just writing this down, because our own society always thinks that the summoned hero should save the world or any case similar to this, like why should he/she? After dragging anyone out of his/her own world, they can at best only beg for them to save them.