Bob, I think you are making a bit too much about this labor issue. Corruption involving Mexico's government makes corruption in the U.S. Government look like a Boy Scout Convention. This is all just baloney, possibly even promoted by Gammon to get the stock down in order to get some large investors in at a lower price.
When the time comes, labor issues in Mexico will suddenly disappear as they have a way of doing in Central and South American countries when serious monied interests appear on the opposite side of the ball.
Powerful Mexicans realize that they don't have the knowhow or expertise to make as much money on their own as they do with all these Canadians down there. As long as they get their cut, they will be happy, and they will do what needs to be done to make sure the "unions" are happy.
Give me a break! Do they even have unions in Mexico?
In the end, the right people will get paid off and mining will proceed as planned.
Of course, that's only my view.
All the best, Bull