There are backroom deals for voting on a bill. People that are guilty probably voted for it knowing it wouldn't pass because they already knew who would sign it who wouldn't... or they sign a bill knowing that they are protected in some way.
Nothing in politics is spontaneous. They have every vote, every word, every... everything pre-planned. It's all for likes and sound bites. he probably signed it with the understanding he would be redacted or protected or taken out of the files. Now he's mad because whoever promised him didn't live up to their side of the deal. Watch who gets offed, they are probably the one who made the deal with him then reneged.