I haven't installed in a DMZ yet, but what the bot needs is to access a Qlik Sense Proxy, the one where the Virtual Proxy is created. So this access can be done to any of both nodes, installed in the same Qlik Sense machine or in other machine with access to the Qlik Sense server.
But the bot also needs access to the Telegram API, and this needs internet access (it works on HTTP). In future articles I will include also Natural Language Processing, that will also need access to the cloud services where the model will be defined.
If you want to use the same Qlik Sense machine for the bot software and you only have access to internet (I think only port 80 is needed) from the rim server, this is the place to run the bot. If you are going to use another machine, this machine has to have access to the Qlik Sense Proxy and to internet.