I'm of the opinion that all slots should open at min bet by default. Is there any good reason why they shouldn't?
The loss of a max bet spin to a low roller is a lot more detrimental than a high roller having to spend a couple of seconds increasing the bet.
Onto this scenario however, I can't see that VS has done anything wrong, if anything it would fall on the provider interface side of things. Looks like user error to me and VS even have max bet protection for you to utilise.
In 10 years think I've only ever had one instance where I set the bet wrong (much higher than I wanted) but luckily bonus landed first spin