You know, I actually think there's potential here, with a few tweaks. Just keep this part in mind:
it is a software product that is used by programmers. Every question about our product is a perfect fit for SO.
As long as that statement is really true, let's consider the following items:
- SE uses it as a revenue stream, and charges a recurring fee for the privilege of using the widget.
- The widget would show all questions from SO with a specific tag on the guest site
- Questions asked via the guest site are automatically tagged with the specific tag
- Questions asked via the guest site also appear on SO. This benefits SO because it avoids fragmenting the community while still increasing it's reach, and benefits the guest because it means more attention for the support questions.
- The price is set in part based on the percentage of questions with your specific tag that get closed. This is done so that guests have an incentive to keep bad questions out of the support site. Personally I'd go for a really large multiplier, such that as the percent closed approaches zero the product is nearly free, but as it approaches 100% the costs stretch towards infinity.