Burton is not the easiest fellow to get in touch with at the best of times and I believe just has a publicist running his Social Media right now. I've not seen his personal account "online" for some time. So no, I've not had the opportunity to get a definitive answer directly from the horse. Not 100% sure if he'd know as it seems that the Quad mixes prior to "Road Food" with the exception of "Rockin' " were done well after the release of the stereo album (obviously); but they were mixed by RCA staffers and NOT the Guess Who's long-time engineer Brian Christian. Even "#10" is not clear on exactly who mixed it as the LP jacket doesn't have any "Quadraphonic Remix by" credits, it just mentions who did the stereo release.
Without Jack Richardson around anymore, I think the only way to get confirmation would be to ask Mr. Dutton to put in a specific request and see what comes back.
I'm trying to get in touch with Brian Christian as his son and a few friends frequent the Steve Hoffman board on occasion. Just playing the waiting game and email tag.
I posted about this previously somewhere, maybe even in this thread, but based on the of the D-V Guess Who reissues, Mike had Sony look for the supposed quad mixes of Paramount and Bannatyne based on the lists I provided, and they couldn't find anything. That isn't to say that they never existed, or don't exist (although I think the mixes of tracks from these albums on Greatest Hits, Vol. II were newly done for that comp based on the master tape box) or were even destroyed, but the current status is "can't find them." Maybe they'll turn up one day, as was the case with things like AF's Loggins & Messina Full Sail (which apparently was lost until it was found) and MFSB's Philadelphia Freedom, which I know took almost a year to turn up...but by the same token I wouldn't hold your breath, it's entirely possible these things were junked at the time if they were never finished.