Transmission replacement at 80K on 2017 V

The transaxles are very reliable. I would try to find an independent hybrid shop for a second opinion. If it needs replacement I would get somebody to swap it for a used transaxle. The Prius v is slightly different than a standard gen3 transaxle, so I would get one from a v, preferably a 15-17 model.

 

Get a second opinion.
As stated earlier, those transmission/transaxles are pretty stout. You may have fractured the flex plate, between the engine & tranny. Did they check the ATF fluid level?
If this was me, I'd find an independent shop to do a used transmission swap. I'm not a big fan of putting used parts into cars, but I would make an exception in this case, again, it's rare for those to fail. You shouldn't have an issue finding one, since they rarely fail. You may just be one of the unlucky few that has a failure.

Hope this helps.

 

Yep, 2nd opinion.

FWIW
Whirling noise while accelerating would lead me too, to drive axles, bearings, trans.
Yet any whirling could be related to spinning engine/ chassis parts, such as the accessory belt area.

If you can DIY here's my 2 cents.
Lift the car.
Place in gear, use some throttle, and while under the car, listen.
Turn the car off, place in neutral, then feel, grasp plus spin, the rims for loose bearings.
Also, look for a torn axle boot or bent axles.
Lastly, drain the trans fluid and look for debris.

Biomed, above has some great comments about a used trans.
Guess that comes down to budget, the difference between the new and used quote.
If the difference is $2K, should you go new?
Also the car value decision; [(current value $15K(?) after $6K trans $21K], so, what's an entire replacement car cost?

Good luck with your decision.