My other gaming passion is Street Fighter. The biggest tournament of the year, Evo, has had the top 8 broadcast on ESPN the past couple years. It's been pretty successful numbers wise I believe. ESPN is obviously open to interesting alternative gaming content.
Here's the thing though: they're not gonna just bring an audience to you, you've got to bring one to them.
When I tune into the top 8 of a Street Fighter tournament on Twitch I'll probably see 100,000 people watching. When I tune into a PAPA broadcast I see more like 400.
Until pinball can successfully bring in the eyeballs and format there's no case to go to a network and say "hey let's partner up here, it will be good for both of us".