Sounds like they were guiding on off reservation tribal trust land, this is a difficult question of legality as these parcels are basically islands of tribal jurisdiction. States differ on how they approach this situation, usually local CO's know those lands well and deal with this scenario wisely. States typically look at these lands as on reservation hunting even though they contend tribal licensure authority does not exist for non-Indians outside of reservation borders.I ran into a situation in Montana in the 1990's with a tribal pronghorn hunt. I was hunting on private land, outside the Fort Belknap reservation on a friends private property. I ran into a tribal guide from the Fort Belknap reservation, outside the reservation boundary, but guiding/hunting a couple sections owned by the Fort Belknap reservation. The client wasn't wearing orange and was hunting under a tag issued by Fort Belknap.
I always wondered about the legality of that?