Since it was sewage, best to not play around and rip up a small piece and check or see if you can get an inspection camera in the area.
Did you actually see how high the sewage water got?
We had some water enter in the basement from the window wells from last summers flood and I did the same (clean water) and it definitely started to mold the bottom of my OSB in the basement
Were just finishing up replacing the floor and re laying new LVP, and we had a dehumidifier and fans running same day and it still molded
#10676714 - 02/24/2503:36 PMRe: Testing For Mold
[Re: SuPeR-MaRiO]
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you can do a mold test to check the air quality and you can also use a moisture meter to see if there is moisture in the area. If there is you'd probably be able to smell it by now (at least in my experience.) Hopefully it's dry and gone so you have nothing to worry about.
I'm guessing your OSB was raised on a membrane of sorts and still got wet?. Ours is this 2in1 Dricore which I dont think raises it too much
We use a similar product but it's called Platon, meant more for exterior foundation but same idea, it raises it around 1/4" off the concrete. We had water pouring in from our window wells so it directly landed on top of the laminate and soaked through the cracks in the plywood.
I had a humidifier going right away and was reading proper humidity levels within a few days, it was dry again after a week but any exposure to water sitting on wood/drywall can harbour mold. It's worse if drywall soaks up the water as it's tough for it to dry out.
Not trying to scare you as the amount of mold we had was very little but it was still there, and I could not smell anything weird.