Welcome Thomas!
Yes we’ve touched on PLF on the forum a few times.
Yes, fluid in middle ear/eustachian tube is a key sign those sufferers do not simply have a migraine!! (!!) 
The extent to which PLF is a permanent fistula and the extent to which is won’t heal itself is contentious, though? I also think the lesion is vastly over-simplified!
It’s very possible Secondary Hydrops may be driving a PLF, without which it would quickly heal. The resolution of PLF may be as much about resolution of Hydrops as it is about a small physical lesion healing. The fact that most patients that have PLF describe tinnitus to me suggests pressure within the inner ear and that suggests hydrops. Obviously the PLF may have been(but not necessarily) the beginning (e.g. via injury) and that upset may go on to form inner ear Hydrops. One can imagine that a PLF might form simply from inner ear pressure? (contentious).
I propose the reason why surgery fails so often is that it fails to address the Hydrops which has formed as a result of the initial lesion.
This touches on an important general point about oto-neurology. I believe far too many people looking at this subject fail to respect the fine balance all the interconnected systems remain in until something traumatic happens and a lot of interconnected processes get knocked out, ultimately leading to migraine. It’s one of the reasons I believe that Secondary Hydrops could be a key aetiology of MAV.
I can tell you from personal experience that the Hydrops can improve significantly. My hearing symptoms have improved to some extent. My ear leaks much less and less often now, but it has taken years.
Interesting, but of course the Perilymph that leaks is NOT blood and has no means of supporting or enhancing a scab, unlike a blood vessel which leaks blood!
My doctor and I believe my ‘PLF’ may have mostly healed within weeks, but leaves my ear Hydropic. This probably goes on to reopen the wound or find a way of releasing pressure itself somewhere else periodically (for me this was every night for 3 years)
I am still suffering after 3.5 years (although my balance has returned thank goodness!)
See some other PLF threads here:
https://www.mvertigo.org/t/another-perspective-but-so-close-to-the-mav-experience-plf-hydrops/15266
https://www.mvertigo.org/t/secondary-hydrops-plf-and-my-3rd-plf-repair/15427
https://www.mvertigo.org/t/ive-had-it-guys-im-going-to-look-into-perilymph-fistula-plf-surgery/13792
James