While playing the game for the first time as a teleporting mage,
I somehow managed to lose dog while teleporting around a few places while trying to find a potion for a quest in Ashbury.
I did little to no fighting during that time, so it's very unlikely he died.
I've tried retracing my teleportation routes - but to no avail.
Even waiting for days at the spot where I “recruited” him did nothing.
I have a save before losing him but that's way back and I'm not going to reload that one.

Is there any other known way to get the dog back?
I'm playing with the latest unofficial patch.

Edit:
I also checked the spot above the bridge, north-east of the gypsy in shrouded hills, where
according to wiki abandoned NPCs may get stuck.

I realized that I used the 'fast travel' glitch quite a bit when traversing big cities like Tarant.
(moving in fast turn-based mode) When using that glitch, NPCs like Virgil often bug out a little.
Could it be the case, that Dog simply bugged out completely by using this trick?