The ability of embassies to affect local goings-on is probably one of the oldest problems in the history of foreign affairs. It's a good example of how it's going to depend a lot on local circumstances. Some embassies are very well placed and have very good relationships and are going to have a lot of influence. In other situations, I suspect that's much less the case.
Again, this points to another obligation for companies, which is to get to know your local embassy in addition to the ways you already do to find out how they're going to be useful in these kinds of matters.