You can bet that if WBGO pre-wired that model for solar they'd not hide the fact. It would be shouted from the roof-tops. If it's not listed in the "features" then it's not there.
I just checked and it appears the 2019 Vista could OPTIONALLY be set up for Solar from the factory.
Solar panel/battery charger wiring prep three-way, solar, plug-ready port located on roof and single port in exterior bay, for aftermarket installation , up to 450-watts
I have the aforementioned "plug ready port" located on my roof and it's easy to spot. It looks like this (mine is white
). If you don't have one of these on your roof you no doubt do not have any pre-wiring installed: