I know if bert wasn't having a holiday at her majestys pleasure he'd have helped u out Harvey...
Also: there would be no gain for TLA. If they succeed GRIND will be gone and cant give them a 'prize'. In fact they could do this challenge without any help from GRIND.Their bet was actually possible.
To get rid of GRIND! completely probably isn't. Some nobles would probably take a week to get to their destination. And before that, TLA would have to clear those villages, and hope that noone supports those villages.