I'll nit-pick a little and say your roof can't delaminate because it was never laminated in the first place, but I suspect you just mean it is coming apart. What you are showing is called a "bubble", i.e.air trapped between the rubber skin and the luan substrate. Yes, if you want you can slit it and insert some EPDM rubber adhesive under it to glue it down. Then close the slit with a lap sealant or roof tape such as Eternabond. It's not really necessary, though, unless the bubble continues to spread. And if it does spread, you should probably investigate why. Water intrusion from somewhere, maybe?