Fillippe says that he's giving Bart a "rifle", but the sheriff identifies it later as a "carbine". They are similar but not identical long-stock weapons, and an experienced lawman would never confuse the two.
Lawyer Fillipe announces to the stagecoach driver that Mr and Mrs Haskell (Bart and Daisy Harris) will be going all the way to Laramie with them. But, the stage is actually going to La Mesa, New Mexico which is close to Las Cruces, not Wyoming.
The scenery also looks to be New Mexico. And the empty grave of John Haskell is in La Mesa New Mexico.