I can't say I'd appreciate the way he made this aid mission so big right off the bat. He's a newbie himself, he knows next to nothing about the world or the various villages. He doesn't know the lay of the land, the local circumstances, the local fauna, the local monsters. He became a sort of an instant idol for slaying the wyvern, but that's it. He took advantage of that fame to get this mission arranged, but no matter how you look at it, it's not really under his control. He has no contingency plans, I bet, nor plans for how to keep things rolling in the future. The villages receiving help and resources now will be happy, but for how long after the retinue has moved on? The villages could be robbed a week later. The resources will dwindle and the poor villagers may be unable to maintain them properly. When you remove the monsters from the vicinity, it creates room for new monsters to wander in, possible even worse ones. In a world with vast wilderness and monsters, getting rid of the beasts is a continuous, never-ending job. Doing it once somewhere doesn't really mean anything, unless it's a rare, especially dangerous type.
I realise my view of it is pessimistic, but I really think he should have just taken a few tough guys with him and got to know the land first. They couldn't have helped the villages nearly as much, but it would have been priceless experience for him, allowing him to build a foundation for bigger things in the future, with a proper plan. Of course a failure would be a valuable lesson for him as well, but it would be hard to bear since it involves the lives of great many people.