Please share your generator.yml you used and the Output of the Generator command which will build the snmp.yml.
Please share the MIBs you used.
Share the Generator command you used with all Flags.
In short the Workflow is.
1.) collect all needed MIBv2 and all their dependent MIBs.
2.) Put all These MIBs in a folder
3.) in generator.yml add your credentials and the OIDs/Names/values you want to collect.
4.) Run the Generator, Point it to generator.yml andthe MIBs folder and it should create the snmp.yml
5.) use the snmp.yml in the snmp_exporter config.
At which step do you have questions and please provide commands, configs.