To add to what @Nash said, I've been the last two years and there's always quite a few breakout sessions in addition to self paced walk in labs and even a DevNET session or four.
Here's what was on the bill for 2019 in San Diego:
Meraki Integrations with the Cisco Security Architecture - BRKSEC-2069
Powerful network automation with Meraki APIs - DEVNET-1217
Building high capacity networks with Cisco Meraki - BRKEWN-1683
Powerful, programmable cloud networking with Meraki APIs - BRKRST-1733
High Density Access Networking with Cisco Meraki - PSOCRS-1105
Simple, Secure, Digital Workplace with Cisco Meraki - INTRST-1105
Taming Branch Security with Cisco Meraki - BRKSEC-2702
Integrating the Meraki SDWAN Solution with the traditional Enterprise network - BRKCRS-2103
SD-WAN Deep Dive: Cisco SD-WAN powered by Meraki - BRKCRS-1579
Delivering an Intent Based Network with Cisco Meraki - BRKCRS-2104
Cloud Managed Security from the WAN to the Endpoint with Cisco Meraki - PSOSEC-1622
DevNet Workshop-Infrastructure as Code 1001 - Network Provisioning, Management, and Monitoring with Meraki Dashboard API - DEVWKS-1069
The Hybrid Campus: How to deploy a combined Cisco SD-Access and Meraki solution - BRKCRS-2105
DevNet Workshop-Infrastructure as Code 1002 - Building, Configuring and Deploying WiFi Engagement Captive Portals with Meraki -DEVWKS-1110
Infrastructure as Code 2002 - Hardening your Meraki Network with Code (and APIs) - DEVNET-2434
Cisco Meraki MV: Camera as a Sensor for Enterprise, Not Just a Tool for Security - PSOIOT-1200
Cloud Managed Security & SD-WAN from Cisco Meraki - BRKSEC-2998
Cisco for SMB Customers - BRKGEN-1003
Expand Your Managed Services and Revenue with Cisco High Velocity Cloud-Based Offerings for SMBs - PSOSPG-1700
If you haven't already you can create an account on the CiscoLive website and get access to the recorded past sessions. Here's the search link I used to get these:
https://www.ciscolive.com/global/on-demand-library.html?search=meraki&search.event=ciscoliveus2019#/
So while there won't be ECMS2, there is literally a ton of Meraki training available. Perhaps that can help you build your case to attend?