Cans are all sealed, but I forgot to boil the closed jars - should I boil them now?
I know the inversion method doesn't involve a water bath, you simply fill the jars, put the lid and band on them, and turn them upside down.  There's question on how safe that is.  (I know you didn't do the inversion method, but it's close even if by accident.)    

I know marmalades can take up to two weeks to firm up and if they don't by then, it's suggested to reprocess them.  At this point, I would say you would be safe to reprocess them.  I wouldn't put what you have directly into a water bath though.  I would pour the contents back into a pot and bring to a boil.  Meanwhile, wash the jars and bands and use new lids.  Then fill the clean (hot) jars and put into a water bath.