Bitpay is easy to use but certainly has many limitations at least on the merchant side.
In my country it has even suspended the bitcoin settlement service altogether.
If your company is interested in investing a bit on the cryptopayment side, maybe can be a more wise approach building your own infrastructure, maintaining a BTCPay server and a Bitcoin full ...
The essential character of money is that you transfer it (or control over it) to another person in exchange for some object or service.
There is no way to use money to purchase something and still retain the money.
None of the alternatives are acceptable to you for various reasons
Invest money in a business and defer purchase until investment ...
Yes, this is a common process used by scammers. It ends up in you paying them lots to withdraw your money that has never been yours without receiving even 1 cent from them.
Don't write to them but seek help from your local authorities.