Can i use a VPN to donate?

I really want to donate to skip queues and check out the trading and stuff, but iv tried using my card with paymentwall which resulted in me losing 20 euros (long story) and i have no idea how to even go about using mint or paysafecard, can i use a VPN to pay with a subway card that i can buy online? I'v checked it out and the subway method comes up when i use a us VPN but was curious as to whether or not it would actually work as i dont want to buy a subway card for nothing, thanks for any help, and if not has anyone got any tips on the best way to go about using mint or paysafecard? IE where do i buy it and how to even use it.
Thanks, matt

You can buy a Subway Gift Card online which the numbers of the subway card will be sent to your email immediately and you can just use that as a way to donate.

I understand that, but what I was wondering was, would there be a problem with me using a vpn to donate? I'm in the uk and there isn't an option to pay with subway card, so I used a vpn to make the website think I was in the US so I could then use subway card, but don't want to waste money on it if there's some sort of restriction. Like do I need a us adress or something? Or can I literally buy the subway card donate with it and that's it