You can use onboard sound in your office as long as it isn't for record. In most cases record will work. I run AvRPS in all of the PD offices so they can check sec tones, etc... I am not buying a Digigram card for a PD.
There are two ways to do this. One is by using DirectX in windows. This is buggy now, as the AV code has progressed. In cases where DirectX won't work, you can use ASIO4ALL and setup ASIO as your driver in the AV2K.ini.
All of my PD offices use onboard sound and all but one (mine) use DirectX. BE will have to give you some AV2K-DirectX licenses in your license file. I'm not sure if they will do ASIO for you. I have been a beta site for over a decade, so I get some favors.
Run setup on your PD computer from Start, Run then type c:\AVSOFTWARE\SETUP.EXE UNSUPPORTEDSOUNDCARDS
In that example, AVSOFTWARE is where you extracted the software. Remember, it won't work unless you get the info in your license file.
Hope you get it worked out. For what it's worth. It never has a problem once you get it working.
I do agree that this should only be done for non-critical systems. IE, not on-air. The fades won't work right.
EDIT*** Okay, I missed your second post. I wouldn't rely on this for recording. Just output. You'd be better off using Adobe to record and AvImport to ingest. Would you explain your workflow to me? I would consider myself an AV expert.