Doubtful.
The lounges are expensive to operate. The theme parks certainly charge a lease fee to
DVC because every square inch of space has value. Plus staffing, snacks, utilities, upkeep, etc.
From DVC's perspective, their main value is to help promote sales of new points. The lounges are a checkbox item that sales reps can walk thru: "hey, if you become a member, we have these three great lounges that are *exclusively* available to DVC!" I don't think adding a 4th lounge really brings anything new to the table. There aren't people refusing to buy now because 3 lounges isn't good enough...but a 4th would finally convince them take the plunge.
What may change in the future is if Disney decides to revamp the Imagination pavilion and the current lounge is forced to close. Maybe then it gets relocated it to another WDW park or a new site within EPCOT.