The payment token is only valid for a specific checkout, and it has a pretty short lifetime (although I'm not sure exactly how long it lives).
Theoretically, you might be able to transfer a checkout token and a payment token, if you wanted to start a checkout in one place, and finish it elsewhere. But I can't see any benefit to this. Once the payment token is generated, you cannot modify the checkout again. And you cannot use it with another checkout. And it would fail if you didn't use it fast enough. And there are probably security risks that I can't identify.
In any case, we don't support this. It's designed for a short communication between the client and two different parts of Shopify, and giving your app the opportunity to report errors before finishing the checkout.
So, in short, the answer is, "No." At least for now. Sorry.