Felt strip under slideout floor loose...

I have a very similar slide system but the underside of mine is covered with the same plastic "rodent barrier" material used under the rest of my TT. That material slides nicely over that white plastic piece in front of the slide. If you recover it make sure the material wraps around the leading edge as you can see in my picture. This will keep the RB or felt from being pulled off easily. I don't think they did this on yours.
You could remove all the felt and install rodent battier or you could cover it with something else - maybe a sheet of aluminum so it wouldnt rust.
I ended up installing rollers for my slide. This keeps the material on the bottom of the slide from slowly abrading.
I used a conveyor roller on each side rated at 1200#.

I'll throw this out until somebody comes up with a better idea:

Run the slide in about a foot. With help (2 helpers best) tip the bottom edge of the slide up by 2 people pushing from inside on the top fascia. Have the other helper slip something like a piece of 2x4 under the bottom lip about 2' in from each end. There is plenty of slack in the slide attachment to do this if you don't get carried away with the pushing.

Reattach the felt to the bottom edge of the slide floor with a good carpenter's glue and run some shims and wedges in to hold it tight against the bottom of the floor until the glue dries solid. (Put some waxed paper on the shims so glue doesn't soak through and glue the shims permanently to the bottom of the felt. I have no solution if that happens.)

I have done this to rescue an empty dish soap bottle that got caught under my kitchen slide and was taking the surface off of the floor.

I didn't say it was going to be easy and there must be better ideas, but it will work.

Good luck.

A

On edit: You could take an Xacto knife and cut the felt off right at the edge of the slide and just not tell her about it.