I have snmptraps and rsyslog for monitoring, the management somehow don't believe things from the AC/AP, as they are data from the "vendor" or something.

All of that failed to prevent that outage. Someone failed to convince your management that the wifi wont go down again..

Monitoring can't possibly prevent outages. All it can do is alert someone when an outage happens.

Based on OP's description, it sounds like that alert will be up to a week late, because the connectivity data is aggregated manually.

His existing monitoring setup has snmp traps n rsyslog involved somehow? It didnt detect the outage soon enough for them to prevent the issue from escalating into...whatever it is now...

I mean...end user complaints is the cheapest kind of monitoring solution but maybe its not politically acceptable?

You could totally do redundancy and failovers and stuff. And perhaps automate some of that. And monitoring is there to detect the "down" to trigger some of these?