Setting up Magento's Payment Bridge with two Authorize.Net accounts

Please note: We are using Magento's Professional Edition which does not come with Vendor Support.

I've looked over previous questions, and while I can find questions and answers about multiple payment gateways on a site, I can't find anything about Magento's Payment Bridge specifically. Payment Bridge is a PA-DSS certified application that Magento provides with it's Enterprise and Professional licenses. It's necessary for a PCI compliant environment.

Our problem is that our client has two Auth.net accounts. This is for reconciliation and the explanation can get long-winded, so please just trust me that this is a necessary scenario.

When creating the merchant with the Merchant Configuration tool when setting up Payment Bridge, it only allows you to provide one login, i.e. just t开发者_C百科he one account, and it asks which cards are accepted. The site will accept all cards, but one account handles Visa, Mastercard, and Discover, while the other handles all Amex payments.

How can I set up the merchant during the Payment Bridge set up to be able to have both accounts?

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Update - for now, we've created a hack in the Payment Bridge Authorize.net class that checks the card type and, depending on the type, it switches the credentials if need be.

Not a perfect solution, I realize, but it's working while we figure out something a little more stable.

If you have any ideas, please share!

Thanks.