I think he has multiple contracts fir each player. Fir 1 yr and fir multiple years. They might not be technically signed yet so there is no violation of the rules.
I think that's exactly what's going on. Not so much with Kadri, as he's a UFA, but with the team's own RFAs, nothing is actually signed. Instead, there's one set of longer term agreements for more money if he can move a player, a second set of short term deals at lower AAVs if he has to kick the can down the road and only can open up money by sending a contract or two to the AHL. Islanders can open up as much as 2.25M more cap space by running with a 21-man roster and shuttling players up and down from Bridgeport. If along the way, someone wants to help us out by claiming, say, a Josh Bailey, that's all well and good.