Alpine wsg for flea infestation?

I've been dealing with a German roach infestation with the help of alpine wsg, but my s.o. now has a flea infestation. I had some extra packets of alpine wsg, so I mixed it up to a 1:3 ratio and sprayed their floors with a focus on the carpet and cushioned furniture.

It wasn't until after I thought to look up a sub reddit specific for flea control and found a sticky on proper control. So, my question is - will the alpine wsg work just as well? I figured I'd have to do a follow up treatment and planned to with an igr (waiting on a shipment at the moment) mixed in, so I want to make sure I'm not wasting my time with the alpine wsg.

Also, I know my s.o. and their roommate (who is refusing to have their room treated) won't go the distance and follow that sticky, which would be difficult with the playfulness of these cats anyway. So, is it really necessary to cover the floors with sheets after each vacuum/treatment?