Re. waitlists, you can waitlist for any CO flight. Likely you would have to ticket something undesirable while you wait for the desirable waitlisted flight--- if the flight clears, then you can change- but change fees will apply. If you redeposit, redeposit fees will apply. There's no free lunch (unless you're Platinum).

Frankly, I would not bank on a waitlist clearing. My experience as a Plat has been very spotty: I've found award seats open up to the general public long before my waitlist actually came through. Saying that, it's wise to be vigilant and check availability often--- especially within 14 days of the flight. Miraculously CO seems to release award seats close to departure--- of course, last minute ticketing fees apply but if you're ticketed already, the last minute fees won't apply to changing dates to within 14 days---- but then, they'll get you for the change fee.

Good luck!