The more I think about this scenario with the boards we have purchased from Jerry, yes a distributor usually does handle warranty issues etc.
However as I said earlier, the MFR is still the top dog on responsibility for the warranty. This is more or less standard operating procedure in the rest of the retail world. Notice a lot of things you buy have a tag that says do not return to your place of purchase, contact the MFR warranty dept first.
I installed a water heater again the other day with such a label.
Jerry, since you are going out of business, maybe you could just tell customers that they need to follow up with IBU corporate for any warranty service.
That way you are not stuck with all the stock you have.
It is kind of odd that so many IBU boards have odd failures in them.