Coolant pump B control malfunction (P261B), Check Hybrid System, and Low Inverter Coolant

I am unsure where to post this as I am new to the forum/website. However, about 2 months ago I drove to a store, spent about 2 hours there, and then when I came back it had all sorts of messages on my 2010 Toyota Prius. Mainly, it said check parking system as it is on uneven surface.. .. not quite that language but something about this. I took it to my local dealer and they said the ECU had been fried, my 12v battery was dead and not working, and a fuse had been blown. Ultimately, I had my 12v battery replaced (I had replaced it a year earlier and had a warranty on it yet), replaced my ECU, and replaced the blown fuse.

Then less than one month later I had a "check hybrid system" light come on along with the bright orange triangle caution light, and the check engine light. Ultimately, I took it to the same dealer who said a code P261B came up and a different code regarding my intake engine manifold. The dealer said I needed a new engine water coolant pump and recommended I replace the engine manifold because, as they said, it cannot be cleaned but only replaced. Yesterday, I spent about $800 to replace the electric engine water coolant pump. I did not do the intake engine manifold because that was going to cost another $600, which I do not have. I picked up my car today, no check hybrid system light nor any check engine light. I drive approximately 20 miles and then later tonight the check hybrid system" light come on along with the bright orange triangle caution light, and the check engine light all reappear.

When I got home and parked my car I looked inside my hood and saw my engine inverter coolant level was right at the low level. Could this low level engine inverter coolant cause all of these lights? If not, any recommendations or suggestions? I am, obviously, taking my car back to the dealer tomorrow. This is turning into a three month, >$1,600 ordeal so any help would be appreciated!