Have a basement pump that stopped working coincidentally after a guest left the house. My guess is that the person may have used a wet wipe or something similar and it's caught in the blades.
The challenge is simply removing the filter from a super tight space. The bathroom is barely bigger than a porta potty so this person would have to remove the toilet, unhook the hoses and then figure out how to pull out the filter for us to inspect it. Being younger, thinner or at least having a good back probably is ideal.
The water doesn't seem to have any significant "waste" in it. It's just backed up because the pump can't push it "up" to send it on its way. I'm no expert but I'm guessing this maybe takes about 45 minutes of work to get it out and 45 to get it back in. Maybe less.