Here I am ;-)
You know, we are honest People and I can say honestly: I DONT KNOW! ;-) No, in fact I must say that I didnt understand everything what you wrote in your post on page one. My english is not bad I believe, but there were so many words and phrases I didnt understand full, so this was the first Problem for me ;-) Please dont Forget, I am not a native english Speaker ;-)
Beside of this, my honest General reply is: We never tried things you want to try / you did. For sure, the "housewife" hint, washing the towels with some added vinegar is well known and we know that this could bring "dead towels" back to life in many cases. So this could be a proper technique to get the last residue out but as said before (and others said): In our opinion a good wash with a microfiber detergent should do the Job.
So what we cannot say because its not "approved" by us is, which chemicals or which ph values are "good" and which are "bad" for example when pre-treating towels. For sure, we used our products with harsh chemicals but to be honest, we didnt do "science tests" in a lab or something. If high concentrated APC (for example Meguiars Detailer APC or others) didnt damage the fabric during Trials, it was fine for us. Our Incredi material for example is also used together with strong degreasers in wash cycles - no issues with that after several Trials.
Anyway, we use our products VERY often in car care and we treat them "normal". That means: Normal use for everything whats needed, normal cleaning with detergents and microfiber wash and normal drying.
We full understand your fears / concerns because products are not cheap and you care much about these things to stay in shape and we really love to see this because its an honor for us! But from our side we would say "Have more fun in USING the products and be happy with the great results and Quality instead of bringing too much science into this". If you pre-treated other microfiber with APC to remove the dirt and it worked - do it with ours too and I strongly believe there is no difference because Microfiber is a very tough and strong material. For sure, if you start soaking a Crazy Pile in strong acid I wont believe it will survice ;-)
Sorry if we cannot tell you more regarding your questions, but you see we prefere to be honest instead of telling you bulls*** or lies.
Hope this post helps ;-)