Might be a great product but again, their web site needs work in clarifying stuff.
When I view info about an older version once found, I see this:
What file types will ON1 Photo 2017 (Photo RAW) work with?
ON1 Photo RAW supports JPEG, TIF, PSD, PSB, PNG, DNG and most raw formats directly from DSLR cameras.
Now I look at the same kind of descriptor for 2018.5, no mention of DNG.
Since it was pointed out the new version supports it, and the old, seems I'm OK but I'll report what I hear back from them.