OK sorry I'm late.  We'll go until noon or so with a few extra clues

Clue #A  The middle knife is indeed Frost Cutlery

Clue #B  The other two knives are from the same maker but different generations--blade markings differ slightly but the same maker

Clue #C (big drum roll...) Two knives are marked "Office Knife" on the obverse of the case.  I would post pictures of thst side and make that the clue but it would show too much.

I have one more clue but it would be like giving things away.

If no one gets all 3 then I will ponder a bit.