If they cheated the space carefully enough, it would maaaaaaaybe work. There is a while unused section of building behind the screen. But I think a full tear-down would be the more likely option. That building is really old. It's been there since the late 70's/early 80's. Fun fact: They build the Shrek walls over the old Nickelodeon show/Rugrats walls.
That's as far as my knowledge goes. It was a rumor that I think was posted a while back. I would imagine it would be something Illumination-related (Most likely Sing). But a DWT Sing show would absolutely make sense for that space. We'd lose an HHN venue but oh well.
While I agree that the Mummy is ripe for replacement, especially with a legitimate coaster likely coming, I think a stunt show would be a horrible replacement for an actual ride. Maybe if they were to use the space to have another outdoor launch coaster, I could see them using the space for both that and Bourne. Plus, the lower lot can get quite crowded, so having a show where the crowd would spill out would be a mess. I know someone proposed on the Bourne rumor thread about putting it right behind Transformers, but it would be so awkwardly placed and out-of-reach from everything it just wouldn't make any sense.
Think about this: With F&F wiping out two entertainment venues, that just leaves WW. They need at least one more entertainment venue to be used for the show, an HHN show, and other possible events. DWT would seem like the most ideal location to do this.
I realize the show will only be five years old next year, but like I said earlier, if you want a daytime indoor stuntshow, a flex event venue for panels, press events etc. as well as a show venue for HHN, this would be the most ideal spot. If they really wanted to carry over the DWT concept to Parisian with an Illumination IP, they can certainly do that if they had the queue and lobby on the first floor and the show and preshow on the second.