Authenticity Question About My Recent Purchase

[theamay]

I just purchased a Rolex watch from a long-time acquaintance who needed money. I paid $2000 for the watch and asked no questions. I have seen her wear this watch for as long as I have known her, 10+ years, so assumed the watch to be genuine.

The crystal does not have a magnifier "bubble" and is scratched. Yesterday, I drove the watch to the nearest Rolex dealer about an hour away to have the crystal replaced. The owner of the store stated "this watch is suspect because it doesn't have a magnifier - this crystal is flat." I said I just figured the previous owner had it replaced with a flat crystal, but I was pretty sure it wouldn't be a fake as I knew she would have had the means to buy a genuine one years ago. The store owner then said that Rolex doesn't make flat replacement crystals, so it's a fake. Of course, I left there broken-hearted.

I just can't believe this watch is not genuine as it feels so heavy and it truly looks real and sparkly. Hoping I can get some opinions -
Here is the info from the watch:
ROLEX
Oyster Perpetual
DATE
superlative chronometer
officially certified
T • swiss made • T
It is all white metal, with 32 small bead-set white diamonds around the bezel, the face is blue. The second hand "sweeps" and it will stop when I pull the winder out. The hands have glow-in-the-dark on them, and there are also glow dots at the number spots. The number spots are diamonds, not numbers.
I removed the band and it is stamped JBJ990721 under 6 o'clock.
There is nothing at all stamped above the 12 o'clock.
There is nothing at all stamped on the back of the watch.
The watch band is stamped "ITALY JBJ", but the second "J" is backwards, "18KT" and there is an outline of what I think might be the country of Italy.
Is this enough information to determine its authenticity, or should I try to take some photos?