Reciting "Ya Salaamu" for a sick person

For the last couple months my grandfather has become extremely ill, me and my extended family have been taking turns in traveling to Bangladesh to visit him. My aunt is currently in Bangladesh. An imam from Bangladesh has told my aunt to recite “Ya Salamu” as a form of tasbeeh 50,000 times. Both me and my mother have not come across this tasbeeh and after looking for it we have not found it, we are both concerned that this is bidah (innovation) and that it is not authentic, please could you clear the air if this is authentic or not.