What is the part number and the e-cad models of the 75-pin connector for connecting the RG191 LoRa module?

RG186-M2RG191-M2

Answer

The Connector for the RG1xx Concentrator Card on the Sentrius RG1xx is a standard PCIE M.2 Key connector.
There are various suppliers for these connectors but the Sentrius Gateway uses a Kyocera, Part# 24 6411 067 401 894 E.

Generic ECAD Models can be downloaded from Mouser