Think about this for a bit. Council, as of yet, has no proof the GRN are as evil as they say they are- no proof that anyone trusts, anyway. The Zoners are pretty miffed, and are taking Council seriously, but honestly that's because A) they're emotionally fragile and B) someone dared to not hand them neutrality as though it was divine right. The IMG may be friendly with Council now, but they're not keen on jumping into a war for them... as we can see from what happens when Council's lines are broken. If a few Gallic miners come out looking nice and peaceful, onlookers will see them and think "aww, cute little civilians, they're not terrifying and evil like Council said". Then, when the GRN bring down the hammer, people aren't mobilized.
A civilian, friendly, "soft and fuzzy" Gallic presence in the Taus is good for Gallia. Even if a few <strike>thousand</strike> GMS workers die in the process, who cares? They're Council sympathizing peasants anyway, it's not like anyone of consequence is putting their life on the line.