Rode many a mile as an employee in a trans dorm, but never with passengers because I worked a train that required a staff large enough to fill the car.
Room 17 is close to the end of the car, so the ride may be a bit rough. However, east of Denver the tracks are relatively straight, compared with the tracks through the mountains, so you shouldn't have an unreasonable amount of lateral motion.
There should be no issue with fumes because the engines' exhaust goes up from the engines. The only door facing the engines will probably be the low door at the B end of the car. All air intakes, plus the side doors, are at a fairly low level so the exhaust should just go over the top & shouldn't be noticed. If the trans dorm runs with the A (high door) forward, it will most likely be at or near the rear of the train, so the engines will be some distance from you.
Regarding the comments about tipping, D T Nelson had it right (above). First-time riders often don't tip because they simply don't know that it's traditional to do so. Amtrak takes a dim view of anything that could be construed as soliciting tips, and people have been reprimanded for it. I'm not personally aware of anybody being taken out of service or brought up on charges for soliciting tips, but it could happen. Whenever passengers would ask me about the tipping policy, I would tell them that according to Amtrak's policy, tipping is entirely up to the passenger. There is no official position on whether to tip, or how much. One of the things that make Coach Attendant positions unpopular with a lot of people, is the fact that tips from coach passengers are few and far between, no matter how much the Attendant does to welcome passengers aboard, help with luggage, keep the restrooms clean, notify passengers of their upcoming stop, etc. Many's the time when I felt pretty discouraged, but the possibility of tips kept me going.
And by the way, I shined many a shoe when I worked the old Heritage sleepers. The more modern cars don't have shoe lockers, so that practice ended with their arrival. After we got Superliners, I kept my shoe shine kit with me for a year or two, but nobody ever asked me for a shoe shine, so I eliminated that from my travel bag. I think the lockers were eliminated because many folks didn't know there was a second locker door that the attendant used to take out the shoes, so passengers would use the locker to store valuables (wallet, watch, etc.). There was a sign saying valuables shouldn't be put in there, but who reads signs? I heard anecdotes about unauthorized people removing valuables (That's a polite term for stealing). Most folks won't want somebody else's shoes; but a nice gold watch is a different matter. Back then, a rookie mistake was to remove all the shoes from the lockers at the same time, shine them all, and then forget which shoes should be returned to which room. I always did them one pair at a time.
Enjoy your trip on the CZ, Liz.
Tom
Tom