Their company is an Eastern European 'SaaS' company whose main product automates blog network deployments so marketers can run campaigns that spam Google's ranking algorithm. SMH. You got banned because you're a spamware company.
Founder here. We're not processing our "spamware" through PayPal, as mentioned in the post:
> The most interesting thing is that we’ve moved away from PayPal in the last two years and have only been receiving some minor payments and paying for a few online services.
We've stopped using PayPal for our SaaS business a few years ago.