My son dropped the Hoover Floormate hard floor

I agree that it is the wheel assembly that's broken. However, my wheel assembly broke in a different place, so I bought a replacement part for $20 or so. I have never figured out how to swap it out...

After a few attempts, I believe it will require some major dismantling and not just a simple part-swap.

From your description you have an issue with the pedal release in the base. this model is the original series, and I would not put too much money in the repair. not an easy cover to remove. check the base wheel assembly. the black pivot points break on these when dropped. If it is broke the part itself cost about $18. Cosider the overall performance and other repair items to determine worthwhile repair.