I think you're in the right track. The name of the siddha in Bangla is Cauraṅgī . What is now the Esplanade area in central Kolkata was previously known as Cauraṅgī (distorted to Chauringhee). The main road that connects central Kolkata and south Kolkata was originally known as Cauraṅgī or Chauringhee Road. It has been renamed Jawaharlal Nehru Road or Sarani. 

There is a brief life-sketch of this siddha in the Caturas'iti-siddha-prav.ritti.  In the Bangla translation the name is spelt Cauraṅga.