Bug: Skeleton Key Vendor Won't Sell Gun Mk2 Blueprints

[isaiaheverin]

I've got the first gun blueprints and then the third from the office, but the Skeleton Key vendor just never made them available in the store, and now at 99% complete on the game, I can't get that last 1% from this bug.

Only slightly happy I got this on Epic Game Store, which doesn't have achievements, so this bug doesn't have to haunt me for eternity.

[Mister Marsteri]

You get the 2nd blueprint from dukes room behind the chair.