attempted to set slaveConnectTimeout: 1200 through both Global Settings and directly in Pipeline podTemplate. I can confirm that the plugin is getting the value, as when setting the value to string rather than int i receive the expected exception error when running the build.
The value is not being honoured by Jenkins though, as the slave node connection timeout is still set to 100.
I need the timeout to be 1200 as my slave on the ARM cluster can take up to 15 minutes to fully connect and register with the master.