2010 Prius sometimes starts-potential parking actuator?

Greetings- I am struggling with my Prius. It’s a 2010 and is currently in the shop due to it’s inability to start or even get ready. I was told it could be the parking actuator which was corroded and if not they would need to replace the wiring harness. This car was considered a total loss vehicle due to hail damage from its prior owner.

It’s giving me the “P brake malfunction get to a flat surface” message. Here’s the weird part.. it can start if left for 5 or so minutes with the parking brake on. Although this is by no means consistent. Once the car starts (orange light, still not in ready mode) I can put the car in park and shift however many times I want.

The “p brake malfunction” error came up out of nowhere on a road trip. Never had any issues with the park button, shifting, and it didn’t make noises.

I bought a new battery and replaced it. No dice. I talked to another Toyota mechanic who explained that changing the parking actuator would not help the car start, so I just feel a bit stuck at the moment.

Just looking for a nudge in the right direction on this little fiasco.
JP