The long answer: "it depends", as indeed the owner of that network, but also extensibility of that network are of huge importance.
EG. If it's your own wifi network (daisy chained) to your local network, I'd simply port forward that cam to your BI infrastructure and off you go.
But that if wouldn't be the case, you might have to reformulate (eg redesign) that other network. One way is to add a (simple) gateway (eg. raspberry pi) next to that cam, and have it VPN tunnel into your network, so that the BI server can talk to that cam. Or, if that wifi network has a "high grade" router, it might be vpn connect to your network and only forward that cam stream to your BI pc.
So tons of possibilities, some easier than others. but ... "it depends"
Unless you know how that "foreign" wifi is setup, this advice can be dangerous, as it assumes that a simple port forwarding to the outside WAN might be implemented, which is, being 2020, the stupiest idea ever...