I. The software is licensed under the GPL (version 2), but the company only releases the source code to paying customers? Is this open source?
Of course it is. But is it an open-source business? No.
Code without community is sterile. It's good for customers because it gives them permanent escrow, but it throttles that benefit by restricting the value of the code. Without a community actively evaluating, implementing, and working with one's code, that code promises to have a short shelf-life beyond the vendor that writes it.
Which may well be InfoSolve's aim. Give customers confidence in the code through what amounts to little more than an open-source marketing gimmick. Ride the open-source wave without getting wet.
InfoSolve's OpenDQ code may well be open source, but InfoSolve's business certainly is not.