First, media partners are obviously going to require a GOR. Why would a media partner be unwilling to tell the PAC that they're willing to pay X amount of dollars if they can get a GOR with their current membership. Even if you're worried that some teams won't sign it, why wouldn't you put an offer on the table? Why would you be at the negotiating table if you can't even extend an offer? It's not even risky; Put a very reasonable timeframe on your offer and see if the PAC can get a requisite GOR.
Overall, it seems a lot more likely that media partners simply aren't offering what the PAC needs to stick together, rather than some sort of weird game being played by the media partners. If the media partners were that risk averse, they wouldn't be talking to the PAC to begin with.