Yes very likely, the round air-cooling holes are a good hint, although they can also be found on the MG30 but those didn't use drum magazines, the MG15 did but it had square air-cooling holes.

Also I think the other models didn't have the buttstock removable while still operational. That's because the MG34 later was often used as a vehicle mg in tanks and the like, where space was limited. During my mandatory service we trained with the MG3 (still in service) which is the successor and basically almost a copy of the mg42 and removing the buttstock would remove the recoil spring.