In case you aren't aware of it, assuming you have tested via Ancestry you have an option to invite people as 'viewers' of your DNA results. This does not give them access to your actual DNA file per se, but rather allows them to view your list of matches, shared matches and associated cMs info. This explains it: https://www.rootschat.com/links/01r67/ .
This can prove useful in a situation such as yours, where having someone with more experience of DNA might be beneficial and/or even just having a fresh pair of eyes look over your results to see if you have missed anything in them, that might prove helpful.
This is well worth considering.
I have access to one of my highest matches' trees & he has access to mine, neither of us have access to the others' DNA, only names & trees.
Prior to us having access to each others' trees, we had no idea how we matched (still don't) but I'm almost there now which is also proving to be a NPE or similar (illegitimate).
I'm no expert on DNA but if I can work through the little info. from my matches' tree & find the connection (part of that tree is also wrong) which didn't help, then I'm more than sure Hebb66 will be able to help you.
I've managed to work out quite a few matches of which another was descended from an illegitimate child.
The chap said he had no info. on his mothers' side, whether it was true or not I don't know but he only had his parents' names in his tree, nothing more.

I done the usual searches, found the death for his mother, was able to get her mothers' m/s & worked back from there with her parents' marriage & bingo in less than 3 hrs

Annie