Hey Dean, having a look through that connector you can do things in any order you want. It is just a function to parse syslog.
You can forward syslog using the instructions provided in the data connector (which gets you to install the agent onto a linux vm, then send the Meraki syslog to the vm, the vm then sends it to Sentinel), or you can forward it up any number of other ways (using syslog-ng, or another kind of appliance you may already have). Then just install the function to your workspace - https://raw.githubusercontent.com/Azure/Azure-Sentinel/master/Parsers/CiscoMeraki/CiscoMeraki.txt
You can install the function without having the logs there yet