my understanding of JMX is that its per VM. With AEM cloud, they will scale up VMs and servers as needed. In this case, how does one access and/or aggregate the jmx info? As Adobe dont offer any sort of monitoring / alerting solution, being able to query the number of errors, or the average time for API responses via jmx would be a good partial solution.
The jmx console seems to be available on local dev instances, but not on any. cloud instances (gives 403)
Is this an adobe hosted cloud environment, or self hosted AWS/Azure environment? The JMX console will be most likely secured and inaccessible by design. I would deploy the prod packages to a lower environment and try connecting there.