Hahahah, oh Mina, you are clever.  Roland kills everyone not on his side in the castle.  As I described, the castle is on lockdown right now.  He claims victory, dresses up some of Richard's men in merc gear and claims that Count Montierro finally made a move and hired mercenaries to kill the king!  The poor bastard had no idea about this coup xD

Montierro is beheaded, pleading his innocence til the axe falls, and Roland, filled with grief from the untimely death of his brother and niece, reluctantly takes the throne.  Life moves on.  Those that still liked and remembered the good Richard did will grieve for a time, but aside from the shadowed rumors of Montierro's innocence and Roland's involvement...nobody will be any the wiser.  That is until Uncle Rodric finds out Gwen is still alive and on his front door step.

EDIT:  And...I just realized we're playing The Lion King.  Uncle kills King and claims the heir is dead as well, then reluctantly takes the throne with everyone suspicious but unable to prove anything, until heir returns with backup and claims his head.  lol oh well it works well here!