The problem is your assumptions. An open convention is not a "brokered" convention. Brokering implies more centralized control. What will happen is the delegates themselves have to settle on a nominee and some of them are going to have to change their votes after the first ballot, once they are unbound. It may not require any negotiating at all to get a nominee, but if there is it will be negotiating between the candidates and the delegates, not some hidden power.
Which leads to the second invalid assumption. The GOPe doesn't dictate the result of the open convention. The delegates will decide. The same delegates that were won by the Trump, Cruz and Carson campaigns in the first place.
So, one of Trump's delegates in my area is the county mayor. Do you think for one minute that if Trump doesnt get it in the first round that the GOPe won't go to him and say, "We really like you and want you to have a bright future in the party but to get our future support you will need to give our guy your vote"?
You are underestimating the party. They can threaten jobs, future support, being blackballed from the party, as well as bribes and promises of all kinds of goodies.
Ted's chances are zero.