Laid up with a P3125, INFO code via Torque Pro?

Mellow greetings,

Last week our 2001 Prius unfortunately gave out on the highway, losing all acceleration capability and the master warning light triangle illuminating. Strangely, I didn't see any codes via Torque, but could be user error. Had the car taken home so I could try and diagnose things there. I installed a new 12V battery thinking that might be the issue, and things seemed OK for about 5 seconds until I pulled out of the driveway: the ICE was revving hard and I barely got the vehicle back in place before it failed entirely and the alert returned.

Torque Pro gave me P3125 (Powertrain). Searching the forums here I realized I need the subcode...probably only available with MiniVCI and Techstream. That's not a problem I can get those. However, I noticed on the PID list in Torque Pro that INFO had been set to 303. Is this in fact the subcode for P3125? If so, 303 (current sensor malfunction) would be consistent with my suspicion that the MG2 stator has shorted rather than an issue with the inverter; despite the prior P3130 it charges the HV battery just fine when turned on, only throwing the code when one tries and fails to drive it.

Being a grad student, I am short on funds and long on the irrational desire to figure things out and fix them myself, but this particular issue may be beyond me. As it is our only vehicle we are anxious to fix it (may not be worth the $ unless I DIY) or find another vehicle. Any advice is much appreciated. Thanks!

A little history:

My 2001 Prius (230k miles) had intermittently showed the master warning light on two occasions, each time right after driving for an hour in the Summer heat with A/C full on. The first time this happened I carefully drove it to Autozone and pulled the DTCs getting P3130 and P030x.

Ah! I thought, the inverter cooling pump has malfunctioned. However, coolant turbulence was plainly visible. Resetting the codes via the battery disconnect method, the problem did not return. The 12V was also near end of life so I purchased a new one, but did not immediately install it.

I perused these glorious forums avidly and have learned a great deal. I purchased an ELM327 WiFi OBD reader and Torque pro, resolving to monitor the PIDs such as inverter temperature and catch the code "red-handed". However the warning light never returned on my watch. Until the above...