At least 25 other members of the Freedom Caucus were prepared to vote against the bill, arguing it didn't do enough to drive down costs.
If this is true, then it wasn't even ideology that was driving the Freedom Caucus. They probably had the exact same take on the AHCA bill as I did: It would be politically disastrous to pass a bill that didn't offer relief in the form of lower premiums to employers and individuals immediately.