HI Morris, I thought the same thing (oil looked terrible!) , but I think the Audi dealer only took a sample of the oil and did not do a change.
You are correct, I think either the cats are deleted or the exhaust is "open" ; , not very appealing.
I believe the interchange was with cam adjusters (I think) ; the exhaust cam position sensor on bank 2 was unplugged when it started.
The oil Level sensor he mentioned , and changed, he thought may effect the starting since he read that the level may be a problem ; his research here on the forum.
yes, rpm reads from a different signal (?) than crank sensor. Compression ok, so just moved on in order to start ; ie most likely no bent valves. Pistons most likely ok since comp. readings were all so close.
Audi dealers typically do not rebuild engines as they offer a warranty so best to replace the entire engine ; where as this garage and owner is looking to save some money and it doesn't sound like he trusts the dealer. It may only need a cam and head or misc. parts. And the garage is willing to diagnose the problem precisely and only change what is needed. Thus, much less than 17,000 bps. !!! 5-6K USD ???? Stay tuned for the next episode!