Although they look wet, they are not actually wet spots, so not
sure what you can do to eliminate them. Does not make sense to me
that they appear in some spots and not others.

I have a playfield protector on my WOZRR which was installed and
shipped from JJP when I got my machine NIB. I have a "wet" spot on
my castle playfield, but no where else on the entire machine. I
have blown air under the playfield protector and it did not help at
all. When the plastic is lifted some, there is no spot to be seen,
but as soon as it makes contact with the playfield in that spot
again, it reappears.

I put a playfield protector on my Flash when I did a full shop
on it and never had a single wet spot.

I have the exact same "wet spots" in between my SS translite and
the back glass at the upper area of the head and they always appear in the same spots where the
translite makes contact with the glass. Nothing wet underneath it
and no oil or residue of any sort. It is just some sort of strange
phenomenon that occurs.

There wont be any issue at all. When I had Flash, I touched up quite a bit of the playfield before putting the protector down. Had it for several years and hundreds of plays. When I sold it, the playfield and touch ups looked just like they did when I put the protector on 3 years prior. The playfield protectors do not move at all if they are fit correctly.