Do you have any info that CS made the 1849 an exact reproduction, including the tang shape?
The reproductions made in India were copied directly from an original. Reproductions of the 1849 have been made for decades. Cold Steel importing a reproduction of the 1849 is using that same old pattern form an original from whatever source is supplying them.
I would point out again that Windlass is not a single forge or shop. They are Windlass Steelcrafts sourcing shops across India and Pakistan. Is CS sourcing these direct from Windlass? I don't know but I know CS is not the only company that is or has sold the 1849 reproductions.
Search "ames riflemans knife" on ebay and note the good, bad and ugly. The good, the correct period scabbard shape/fittings. The bad, aged and "fakes". The ugly, rough approximations. The good and bad, all from the pattern from an original that has been reproduced for decades.
The CS 1917 Frontier was not based on the decades old reproduction Ames 1849 Riflemans knives, hence the tangs are not going to be the same. Can you make CS 1917 Frontier grips fit the 1849? Why bother? The 1849 has a narrower profile, so sure. Will the holes line up? Probably not. Are the screws bigger in diameter than the brass pins in the 1849? Yes. Can you strip the 1849 and add whatever you want to? Yes.
The old reproductions do turn up aged and sell to fool. Cold Steel has forgone having Ames marks added and that's a great thing. Aside from the grind being wrong, the pins are wrong, the guard is wrong and the lanyard solid brass tube is wrong. The current CS reproduction is coming with the same type of scabbard and fittings as the fantasy 1917, so that will be another tell. The older reproductions and those coming new from other sources will show much the same faults, with the more correct scabbard having staples instead of rivets on the scabbard fittings.
Cheers
GC
Edit, I could add other physical and visual differences between the CS and others (Dixe GW for instance sells a ringer). The CS is actually doing a good thing with eliminating marks and some subtle contours here and there. Overall though, still that same old lump of steel

Might be better steel.