Probably not.Her marriage to Edward IV was scandalous at best since she was pretty much seen as a commoner.It would have been a step down for either of the brothers(even if their older brother doesn't mind,it doesn't mean they wouldn't).There's also no gain in marrying her elder daughter by either George or Richard since she wouldn't have been an heiress of any land.The marriage most likely would have been illegal and would require papal dispensation.I don't think either of the two brothers would bother entering marriage with a minor noble/commoner with very little benefit but a loss in both prestige and most likely money to the pope for even allowing such a marriage to go through.