if the uscis put you in a removal proceeding,even you send your i-751 to them that you application will be denied. then you have to file the motion to reopen.
i think you should try to talk to an immigration lawyer and file i-751 with a reasonable explanation why it is delayed as soon as possible
i think you should try to talk to an immigration lawyer and file i-751 with a reasonable explanation why it is delayed as soon as possible