It's hard to say if they'll be "tossed out". If an airline were to be kicked out simply because it was in bankruptcy, most of the airline alliances would probably have fallen apart a long time ago.

Here's what my crystal ball is saying:

1. MX reaches an 11th-hour deal and gets financing just in the nick of time to stay afloat. A restructure will follow. Routes will be cherry-picked and there will probably be some routes that will be given over to oneworld partners (or others) to service.

2. MX stops altogether with little or no notice. Within Mexico, other airlines might be required to honor Mexicana's domestic tickets on those routes which are not served by either Click or Link (assuming they still survive). But, if it's a route that only Mexicana served, the ticket holder is probably out-of-luck.

Outside of Mexico, possible that oneworld will honor the tickets to maintain the integrity of the alliance as long as they already fly between the origin and destination indicated on the ticket. If not, too bad, or they might offer another nearby airport if they're in a good mood. Slight chance that non-oneworld airlines might honor their tickets (but I doubt it).

3. MX stops. Mexican government does nothing for internal flights, not even require that AeroMexico, Volaris, etc. honor the tickets. You're walking or on the bus amigo/a!

But again, internationally, I think that oneworld should do the humane thing and step in and honor those tickets in some fashion.

4. Stay tuned. This could get interesting. I'll see how I'm going to get back to LAX on my one-way ticket from MLM in February (found a fare that was too good to pass up!--going down to MLM on Volaris). Haven't started my trip yet, so I'm not losing any sleep. My bet is that in the case of a financial rescue, the only thing I might be facing would be a schedule change. In the case of a shut down, might fly back to LAX via AA (change in DFW) or AM (change in MEX).

Flew MX to El Salvador a few years ago and really liked it. ¡Viva Mexicana!