I could see this Young Master being a fruitful seed for future developments, if Just The Heir wins.
It's not generosity. Undeniably, if the project is successful they benefit from it - they benefit from having the prestige of helping restore Waystones, or even create new ones if we get that far. Politically, that's pretty strong even if it gets restrained to just Laurelorn. And that's only if things get that far! This isn't an intern working for exposure, it's a political move calculated to be minimal-risk. Worst case scenario for them, the project goes nowhere and whoever gets chosen to help with it loses 'just' a few years of effort.
None of this is bad - the basis of trade is mutual benefit, and certainly we'd both benefit from this. But it's not something they're doing for no reason.
Unless the shrines to Hekarti mess with the Waystones somehow (in which case we'd have sufficient grounds in which to say Tindomiel made the agreement in bad-faith), then the worst that they are is a political move.