It would be tantamount to an international incident if the players refused to play because they didn't like the field conditions, especially if a herculean effort to get it as good as possible was performed.
And players who refuse to play would be suspended without pay. That might work for multimillionaire players, but not for the average roster player.
This game is going to happen. The NFL will say all the right words, and you can bet that team reps will be informed that the players had BEST be gracious about it.
All that said, I don't like it. And I don't like regular season games being played on foreign fields.
God forbid that some high profile player blows out a knee because regardless of reality, it WILL be blamed on the field conditions and I can't even imagine the uproar from the Players' Union and probably the tangle of lawsuits.