Well, here's the pledge Trump signed, and it seems pretty clear to me. I don't see any asterisks with a side note about anything else being promised to him in return.
When interviewed by a Town Hall reporter, Trump said he had "no intention" of reconsidering the promise: "I see no circumstances under which I would tear up that pledge," he said, calling the pledge "total."
I understand he wants to be treated fairly, but that didn't become a condition until a month and a half after he signed the pledge. His position seems a bit over conveniently flexible. I've known people like this before, and I don't trust them.
Having said that, I'll vote for whoever the Republicans nominate, because to do otherwise is political suicide.