I recommend against streaming in an office environment. In fact, I forbid it in my office environment. The cost of the extra bandwidth necessary to support multiple streams is usually much more expensive that most cable company Business TV plans and there's no futzing with extenders, video routers and switches.
If you have unlimited bandwidth and don't plan on using it to accomplish business goals, then it comes down to how you might control it and that's typically not trivial for streaming sticks and inexpensive streaming boxes that only support on-lan control.
I'd suggest an alternative of using cable TV in association with a Harmony Smart control and a couple of IR blaster cables. That way if they want to watch something else, they can take a remote out of the company safe and change the channel.
Plusses:
- Consumes zero broadband bandwidth (this is especially important if you had designs on using Wi-fi)
- Few additional parts (if any) and no long, expensive HDMI cables and switchgear.
- No jumping from a different TV service to station website and back to find the channels you want.
Minuses:
Dealing with your cable company (assuming you don't have to do that for other reasons anyway).
My local Comcast offers Business TV for Offices for around $25/month and that's probably cheaper than a business-grade streaming service that gives you all the channels you want.