Colt has not for many years marked the engravers name on the firearms. It is done that way on purpose. Call and ask if there is any doubt.Interesting. I doubt this is new info for anyone. A 1994 gun that is simply "Colt Engraved" should be marked on the trigger guard under the grips as "Colt Engraved" and no engraver's initials or signature. On the other hand a "Colt Master engraved" gun should have both the engraver's signature and "Colt Engraved" on the front strap of the trigger guard.
Th archives letter should be specific on both counts. No engraver listed for a "Colt Engraved" gun. Master engraved will generally have the engraver's name on the gun (often in more than one place) and on the Colt letter.
4 years ago ...which clearly is not 1994.... a "Colt Engraved" SAA gun at a D level just for the engraving was $3600. A master engraved Colt @ D level, engraving only was $13,000.
I'd likely want to check and then photograph what is under the grips.