Harvard does not make the chems here being asked about.
I believe it was a Steam way product I had won many years ago that also claimed had a protectant in their rinse... But I never tried it way back then...
I prefer not to run a polymer rinse through my truckmounts as in some experimenting we found they would plug up the units especially at higher heat.
I have used a polymer rinse once on a bad powdered carpet deodorizer job... Seemed to help but Descaled after that job.
I prefer (and so does Harvard) to apply a protectant that old fashioned way yet (after cleaning)
It someone could get some product it would be interesting to see it's performance... But I would only practice on an old scrap sample or your personal home vs sell magic pixy dust protectant (
@Jimmy L influenced here) to your clients...