Muslims are not opposed to the N deal. The ulema recently clarified it when some parties tried to the muslims into it.
Same with the Amarnath shrine issue, the news about thier stance was there on rediff.
Vande mataram means worshipping your mother; in this case the motherland. For muslims to worship anyone other than Allah is tantamount to disbelief. For them it is Vande Eeshwaram. Nevertheless as a national song, I have no problem if you sing it. But if I were to do it then it would be hypocrisy or coercion. We must be honest about our national feelings.