BoulderGal, welcome. Sorry you're having so many problems. This forum is a great place to get advice (sometimes maybe too much advice
).
First a disclaimer on my part, I'm not familiar in detail with the 178 plumbing routings, I have a 179.
Next, a dumb question, has it been raining while you've been there? You're obviously having plumbing difficulties but let's also rule out other sources of water intrusion.
Third, my recommendation is to actually look at the fresh water tank under your rPod and not trust the little sensors, they can be inaccurate. The fresh tank is translucent so you can easily see how much water is in it.
I believe all your plumbing equipment is in the rear of the 178 so if any of that is leaking then the water can run all over the area under the bed and in the storage areas. Enough water to get the tips of your fingers wet is a lot of water if its spread out back there.
A couple of things you should do right away. Don't reconnect the city water. Run some water out of the fresh tank if it is full/overfull. Then, leave the water pump off. You want to stop any more leaking before you have more problems due to water damage to the floor.
Pull up the mattress and plywood to expose any wet areas around the furnace/pump/water heater area and dry up any visible water there and in the underbed storage. Get a little portable electric heater (assuming its not warm enough to just run a fan) and try to use it to get everything dried out.
All the above is to try to get things dried out, it won't of course stop the leak itself. So getting back to that most likely the problem is that the check valve in your water pump that keeps city water from flowing back to the tank has failed. Usually that will result in the tank overflowing out the tank fill fitting but you're getting leaking elsewhere. And the usual temporary fix is to do what you already tried, just stop using the city water.
That might have already worked and you're just seeing residual water from before you shut the city water off, or from the tank being too full. Or, you could have a leak somewhere in addition to the check valve problem. Either way, I think you have to get things dried out a bit so you can find out if there is still a leak and where it is. The pump itself and its fittings is a good place to start.
Good luck, and others as they come on line today will have additional suggestions for you.