A RS-1, eh? That's a olde but an original goodie. 700 lumens @ 15K:1 Contrast
I know it well, having done several systems with it, including an incredible 215" Drywall screen.
But I used a Mix called S-I-L-V-E-R, a high gain, spray-on only application for that monster.
At 92" diagonal, and if you can place the PJ at a throw distance between 9.5' & 10.5', you could use Silver Fire v2.5
with no added colorant and get spectacular "Interstellar Deep Black" results without sacrificing one bit of lumen output doing so.
My only real concern is that you opted for BOC, which is in fact a more labor intensive material....one that needs to be primed and sanded before you apply a high contrast, high resolution Paint via Sprayer. And SF
does demand spraying.
Flexi-White would have been highly preferable, and frankly speaking, at the screen size your doing, switching over would only cost $54.00 (shipped rolled on a Tube) and the resulting ease of applying it to a Frame combined with the lack of need for priming / sanding would make it a worthwhile investment.
And...if you purchased a stock-sized piece of BOC ( 66" x 110 ) for $39.95 and have not cut into it in any way, a Call to Carl's Place requesting an exchange will undoubtedly be honored (...and if your BOC came folded in a box, it would be advisable in any case...) Just tell 'em Maurice advised you to switch up and just maybe they will comply with no issue at all.
There it is....my best advice. Run with it...or run screaming the opposite direction.