Not sure if its blown or not. 130K miles

A Few months ago my daughter was driving a mile from the house and she heard a 'bang' (not sure how loud or what) and from this point on the car went into (I think Limp mode) and drove very slowly back to house. I ended up getting her another car just cause of it....

There is no Check engine light on or Service lights of any sorts, it will shift into and out of gears, but will not drive. Ive disconnected the battery and let if sit about 5 mins to reset any computer issue, maybe need longer?

I did speak with Nissan and of course 4k to replace the transmission, 3K at a local place with no Warranty or even anything because he told me flat out, and I asked for an honest opinion, He dosen't like them and doesn't trust Nissan's CVT...I can respect that.

Is there something stupid what would make it do this, there was no sign of any other issues, no grinding, no nothing....

What can I check for?

I believe you'd mentioned that this car was purchased used, correct? At 130k I'm willing to bet the CVT is toast. Check with a different Nissan shop to see if they've got a better rate. If you want to go with an independent shop you should be able to find one that will offer a limited warranty, usually up to 60 months.