Hi Arie.
Glad to hear you got it sorted. I would say you're right about a QC issue as a FR's (and licensed ones) saddles should be the same height (thickness). Just one more thing I dislike about working with them, but anyway...
You can buy shim sets for them but they're over 25 bucks for a set of 12.

In your case with one saddle being higher than the rest, I would have considered lowering the high saddle by filing the bottom instead of raising the others to match.
You didn't say whether you created a radius with the copper shielding tape, and I know that wouldn't solve the radius issue, but lowering the high one would give you a level start (sorry for the pun) and reduce the amount of tape or shim material under the saddles required to achieve a radius. 1.2mm is a lot of copper tape IMO.