UPDATE: Our van blew up, what do we do?

UPDATE: Thank you all so much! I got great advice from this sub.

When our van's transmission started to have issues I took it to a garage and they quoted me $10K to fix it and recommended that I trade it in for a new van.

This sub rightly called that a "Fuck off quote" and recommended that I get a 2nd opinion, possibly from Aamco.

I took it to Aamco and they found that the computer system in the transmission needed a software update: $400!

We're freaking saved! Van is fixed!

Original post below:

We own a 2017 Chrysler Pacifica that's paid off that we completely depend on: it's our family van!

Well, a week ago the check engine light came on and suddenly it won't shift above third gear. I took it to our local garage and the guy quoted me $10K on a transmission code and when I asked him what he'd do in my place, he said "Trade it in".

We're currently looking at that, but my question for yall is:

What is the smart and efficient approach to getting a family van? Do you go new? Used? Toyota? Mazda?

Is there a consensus right and most economical answer?