Other Configuration Manager-related features and issues
There should be a status message that tell you when ConfigMgr Push stops trying to push to the devices and therefore you can set an alert on that. But that will happen after 7 days.
Also if you setup a Fallbackstatus point, if the ConfigMgr push fails on the client side, it will return a message, again you should be able to setup an alert on that to.
This is all in theory, I have not tested either option.