"Sorry if the pictures weren't clear. We are giving CarPlay demos in the sound proof booth here at our booth and wanted to share our marketing activities at this event with our followers. We are eagerly awaiting final certification for Apple CarPlay and of course we will let you know as soon as it becomes available."
So pioneer is being held back by apple. Is it because their update isn't good enough yet? Is it because they are letting Ferrari or Mercedes launch their car first? Who knows. However it is apple that is holding back the update. This is why they don't have a date to give us because only apple knows when that is and they aren't talking.
I think the answer is a little simpler than you suggest with your questions. It is "awaiting final certification" by Apple. This is not a terribly new thing in the electronics industry, especially when you are partnering with another company for a project such as this. This statement confirms that Apple required that partners get their implementations certified before releasing them. That means testing, including tests against certain quality bars (MTTF/MTBF numbers for example). Issues found are reported, and usually required to be fixed before launch. Once it meets that bar, it is certified and ready to go. To be honest, I'd be more surprised if Apple didn't require this. They have their "Made for i" licensing program which would likely require similar certification, and I believe I even read an article around the time the lightning connector came out saying that Apple was getting more strict here.
The cellular industry works on this very principle. If you want to partner with a carrier to sell a phone through them (in order to get the subsidies that make it more attractive to buyers), you also need to pass their certification process before they will sell you in their stores.
Of course, awaiting final certification doesn't mean "imminent release" either. If an issue is found, and required to be fixed, it could be weeks of turn-around from having to certify a new build. If I was Pioneer, I wouldn't be giving dates out at this point either, for that very reason. Not unless I wanted to tempt Murphy's Law.