I've had some success with severely corroded "dead" boards using my own solution of distilled white vinegar, 30 vol hydrogen peroxide and a tiny pinch of a mild salt such as "Lo-Salt" or if you can get it KCl.
It appears that this actively strips corrosion without damaging the tracks, and in some cases actually brings the board back to life for a while at least.
If board looks OK after this treatment do the usual rinse-in-DI-water-then-IPA method and see if it works.
This is a last ditch remedy but worked a few times for me even on R/C stuff.
Interestingly there is now a commercial solution based on my work, go figure.