It would be way easier to just use the client task "install software", which you can use from the comfort of your ESMC without having to manually connect to all of your clients networks. Why have a Remote Management solution in place, and then not use it?
So when you're working for multiple clients, you have to manually connect to their networks and use ESET Remote Deployment from one of their devices. If I understand you correctly, you have >2500 Clients in your console, across multiple networks I guess? ESET Remote Deployment works by sitting on a server (or any other client which reaches all the devices) and deploying the installer and the associated commands over your network. Is there a particular reason why you do not want to use the tools given by the ESMC?