Stripe considers using a real card to test a zero-tolerance fireable offence.
I, as the name on record for an organization with Stripe, made an actual, legitimate payment to said organization (and did not refund it). Stripe's automated system caught the payment and terminated my account automatically by the time I woke up the next morning; fortunately I was able to reach a real human and explain that in addition to working for the non-profit, I was also donating to it, and they begrudgingly restored the account.
My company has hundreds/thousands of ecommerce clients, of which a huge portion use Stripe and we do real card testing every time we deploy code that could affect payments and its never been an issue.
I, as the name on record for an organization with Stripe, made an actual, legitimate payment to said organization (and did not refund it). Stripe's automated system caught the payment and terminated my account automatically by the time I woke up the next morning; fortunately I was able to reach a real human and explain that in addition to working for the non-profit, I was also donating to it, and they begrudgingly restored the account.