My take is that DEX Inventory is Diamond owned inventory and weeks that they've taken in for exchange from members (like a Wyndham PIC.) If these are affiliated with RCI then the answer is yes, BUT you're not exchanging for RCI inventory. I really think the program sucks, points for tiers are way to high and it's confusing to the point that you don't understand how bad they're milking you. Coupled with things like loss of provided Interval Intl membership, loss of many, many resorts not included in 50% late reservation discounts, no longer being able to upgrade once in the late reservation discount window, etc. They doing away with all the really good stuff and making it all smoke and mirrors for the salesman to confuse you even more.