GST Registration liability for Commission Agent/ Intermediary

Sir,
I am a Bhilwara based commission agent or we can say an Intermediary who only sells grey fabric on behalf of weavers/suppliers and receives commission on the basis of sale. Not involved in any billing from Supplier to the Buyer. Simply receive commission. Also our turnover does not exceeds 20L threshold turnover. Now, i have 2 confusions in my mind which i need to get cleared:
1. Turnover does not exceeds 20L, so not liabe for Registration. But being an Unregistered Agent, Will the supplier be liabe to pay GST on our behalf under RCM? And will he deduct the amount from our actual commission?
2. If we get registered, and still have turnover under 20L, we will receive full commission from the supplier. But will be be liable to file return under GST, and turnover exemption will not be applicable?

Kindly help me out regarding this issue ASAP.
Regards
Vivek Sangtani