My guess is they will be compartmentalized to their own unit(s), with dual speakers coordinating with Russian units/leadership. Though, like you say, there probably aren’t very many of those, so these units will be particularly at risk if their rare dual speaker gets taken out. They could probably mitigate this a bit by having dual speakers in safer locations one tier up the command chain.

This all assumes they will be in front-line roles. It is possible they will get assigned to safer duties, freeing up Russian soldiers to go to the front.