I think it would be fine. Rory has nothing to lose- if he loses, it's to highly regarded Mousasi. If he wins, he vacates WW title and moves up to defend his new belt. For Mousasi, a win over Rory means more one too name added to his legacy. If he loses, he remains a fight or to away from a rematch. Plus, he knows fights against Lovato Jr or Tokov are risky, because those guys have the skill to beat him. If he loses either of those fights, this fight with Rory might be off the table for the foreseeable future. Best to ask for it now.
Although this isn't a far-fetched pov, imo, it isn't going to happen anytime soon, and after the beating Lima put on Rory, I'd hate to see another by a far better fighter, which holds up two divisions, and then have Rory come back down to a possible rematch with Lima, or even worse, Koreshkov.
The way Bellator is (more aptly, aren't) marketing their non-fluently-english-speaking champs and contenders, if Rory gets his ass handed to him by Moose(likely), then comes down and gets his ass beat by Koreshkov, then Lima, I think he hangs them up. If he stays at WW and gets paid decent enough and just loses a couple at WW, I can see his fire still there, and I doubt he takes as serious a beating in the WW division as Mousasi is likely to hand out.
I agree that Lovato and Tokov are risky for Mousasi. Certainly Mousasi/Rory is financial a home run for both guys as well as fans, this is just one of the rare situations where I'm concerned about the business side of it, as Bellator has been living in the red since Coker took over.
If Mousasi loses, I don't think he fights twice before a rematch, I think it's once at best and possibly immediate, which holds up things further.
I also think Rich Chou and Coker are realizing this as well as other outcomes, hence the reconsideration and brake pumping.
What none of us wants is another long waiting period of inactivity surely.
