I'll take a stab at this. :)
Partially because the vendor (Cubic) hasn't yet met the requirements of the system, particularly the zone system and tap-in/tap-out reliability and timing. I've heard (note: this is just what I've heard, don't take it as absolute fact) that some of TransLink's back-end systems are running OS/2, which probably isn't helping matters.
No one person. And I can't find any details about the contract signed with Cubic to find out what kind of penalties they would pay for delivering late. I would hope that Cubic would have to pay some kind of penalty.
Because if he was outright fired then TransLink would owe him more money for prematurely cancelling his contract. He was hired on a contract, and because of our legal system TransLink needs to adhere to that contract.
Partially because monetary considerations aren't the only benefit of being the leader of a country. Partially because in the private sector CEO compensation is incredibly high (the CEO of a similarly-sized company to TransLink would be pulling down at least double what TransLink's CEO does). And if you compare his salary to executive pay in other public sector jobs in BC, he's at #39 and is the only TransLink person in the top 100. There's room here for a greater discussion about executive salaries in general, but that's a separate discussion.
Currently unknown what powers Mr. Pattison will have. However, in a similar role during Expo 86, he wielded quite a lot of power, even though he wasn't an elected official. He made architects, designers, and builders stick to the plan with the money they had, and did an amazing job. There is nothing here that indicates he'd do any differently than that. He's a hard-ass, wields a lot of influence, and if anybody can make contractors stick to a budget, it's him. Edit: this just in: the Mayors' Council has released the terms of reference for Mr. Pattison's position.
I think the naming of Mr. Pattison to chair the public accountability committee is a huge step towards reassuring people that the money raised will be well spent. In fact, voting 'yes' means that:
a) the public accountability committee is set up
b) all the money is independently audited yearly
c) all the money will go directly towards these transportation improvements and nothing else
Voting 'no' means none of these happen, so if you want TransLink to be held accountable, you'd vote 'yes'.