Just look at most UK Government IT projects. They've got it down to a fine art, blowing billions and being left with nothing useful.
Several major international government consultancy firms got their break on supposed small UK Gov IT projects, and were able to keep billing $1,000's/hour for years (while delivering nothing useful) and became big IT consultancies in the process. The failure didn't harm them one little bit - it let them claim the have experience and that got them way more work.
IT project failure in large and complex organizations is practically guaranteed.
Now, if they did that small-ish team, paid well, it could well work. But your board is not going to approve some pizza munching, jolt cola drinking geeks as your wonder IT team. Don't worry what the team is really like, the consultants asked by the board to review them as part of the process will make sure they're described as the aforementioned pizza and cola weirdos. And recommend using the consultants team instead. Been there. Done that.