I don't find this off topic at all. intercom is a often overlooked but ESSENTIAL part of making a successful broadcast.
the tw-47 you linked is really meant to interface to a 2way radio. the ef-701m is really what you want from clear com. better yet, we use the studio technologies model 45/46/47 units as they have much better performance and features.
lets assume you have a simple belt pack coms system that uses 2 wire (both talk and listen share a single circuit on one pair of wires and the traffic is bidirectional). most audio over fiber paths are unidirectional (one way only) and don't pass any of the required power for the belt packs. you need a 2 to 4 wire interface on each end of the fiber to convert the single bidirectional circuit into 2 unidirectional circuits-one going each way. then you just need an audio path both ways in the fiber for each channel of coms you use. the interfaces mentioned above do just that, as well as taking care of handling the power, stripping it off one end and adding it back in on the other end of the fiber so your belt pack still works. actually if you use the CC unit you have to add a power supply to the remote end as well IFIRC.
this may sound overly complicated, but with the right hardware it works very well. we can put miles of fiber in the middle and the other end sounds like they are in the same room. we have built dozens of systems that work this way, very reliable as well.
other options...we are moving a lot of our systems over to dante, an IP based audio standard. there are dante intercom belt packs and interfaces to make this happen, and even units like the Studio Technologies Model 45DC or 45DR that bridge the gap between dante and analog. a dante intercom system would only require a network connection over fiber to connect everyone and POE switches or injectors handle powering the belt packs so they only need a single cat5 cable to function. we also have fiber interfaces that will put more advanced intercom panels, like the RTS ADAM series, onto fiber seamlessly.