@jmorphew - you are trying to apportion blame on others when it is your company's process that was at fault.
First, if your company's suppliers were listed as administrators, they would have been getting the warning emails. We are a Cisco Meraki reseller, and we act on every licence and shutdown notification we receive on behalf of one of our customers. Everyone of them.
I can't understand why a Cisco Partner would choose to ignore such notifications, knowing what would happen to their customer.
Perhaps you could start by asking those suppliers why they ignored the warnings, why they didn't reach out to you and take care of you.
Who originally setup your Cisco Meraki network? They should have known to setup the notifications to a monitored email address. It's not just licence notifications, but other critical notices (like security notificatoins). Someone should be reviewing them.
Cisco Meraki clearly spell out the terms and conditions (such as in the FAQ posted above). They send constant notifications to all the registered Meraki account admins.
I really can't think of what more Meraki could have done here. They did exactly what their FAQ says they do. They did what their T&Cs say.
Their is nothing to escalate. The Cisco Meraki process worked exactly as intended.
At the end of the day - it was your company that made the mistake. Loading in devices rather than the order number, only having notifications being sent to people that ignored them.
It is your process that needs to change.
I understand you are feeling pretty savage about what happened. You had a complete network outage due to several humans making a mistake. And that is what it was - a human mistake.
And it wasn't even just one failure - it required all of those people getting the warnings to ignore them. If only one of those people had flagged it with you, this issue would not have happened.
You can keep using SAML. That is a good approach. You just need to configure the notifications to be sent to a monitored email, talk to your suppliers and ask them to never ignore such emails again, and move on.
I'm sorry for what happened to you - but this is the cold reality.