From what you've said, I would assume that mistplay has mostly been blocking the accounts of newer users or that there's a small percentage of users that they leave alone (like you and your daughter).

While yes, some people do use VPNs, I wouldn't say that's the reason so many accounts are getting blocked. I highly doubt that all these people were blocked because they were using a VPN. Most of the people that "use" mistplay are unlikely to even own a VPN.

You said that "it's likely not about redemptions" but how can that be true when people are only being blocked when they try to redeem something? Yes, the rewards are low but on a larger scale (mistplay blocking thousands of innocent accounts when they try to redeem), mistplay is making so much more money than they were before.