What is the problem?

Why don't you just connect your old Presonus card to the RME RayDAT?
Why this strange remark about RME lobbying their products? What should RME recommend to you apart from RME products?

Sorry, but all sounds a little confusing, please clarify what your concrete demand / question is.

That's what i wanted to do and did when i got my raydat card.l. This is my 1st venture into pcie cards so I'm not exactly sure how everything works.

The strange remark was because i told rme directly in an email i was planning to connect my presonus to the radat card via adat. they wouldn't say yes and acknowledge that would work, they had to lobby their products to go along with the raydat card which would have cost me more money for no reason when i had something that would have worked and they knew it would work....not cool.

I total agree that rme products are superior to presonus and so far i love my set up though i think i need a faster computer to take advantage of the raydat's speed/low buffer settings. Im running a dell t7500 workstation with duall Xenon 3.4gzh chips and 24 gigs of ddr3. I'm finding out that server chips are not the best for recording...
You've responded to a few of my posts and i do appreciate your help as always

It is not the task of RME to recommend third-party products. Such a recommendation is accompanied by a certain responsibility that the setup works like this.
As a company, they can of course only guarantee this for their products.
They even recommended products from their portfolio to you with a sense of proportion, which are not too expensive at all. Even a card that is no longer manufactured and is only available on used market. Normally, no company makes such recommendations to use something from used market. Therefore, I think there is absolutely no reason to complain.

Like Vinark told, you can use the Presonus as AD/DA converter card. Maybe even in stand-alone mode, if the card allows. Otherwise, you need to keep it connected to the PC via Firewire.

I don't have English as a native language, either, and I found this thread hard to answer.
Many of his requirements are still unclear.

To find the best matching solution would have required further details about his setup and requirements.

Unfortunately, he did not work further on the thread where he asked for help: https://forum.rme-audio.de/viewtopic.php?id=36527