I'd be amazed if Cortex could get the RD rights back - first off, Cortex doesn't have any money to pay for them... and due to sheer human nature, Valeant would be reluctant to let them go for a lot less than they just paid for them.
I'd also question the benefit of spending much to get the RD rights back... RD was difficult to sell, most here seem to agree that even if viewed as promising, these SA results aren't going to bring a deal - so RD and SA combined don't seem to add up to a package that would be very marketable either.