You're missing my point. While a truly catastrophic event such as you describe would probably rapidly erode the value of the US dollar, such valatility is common to Bitcoin even lacking catastrophic events.
If your company started paying you in Pesos (fixed at todays exchange rate), and then continued paying you in Pesos going forward you'd still be subjected to far less volatility than what you'd currently be exposed to with Bitcoin.
Your main issue with being paid is Pesos is because they'd be a pain to exchange for goods and services in a country where they're not legal tender, not beause of any inherent instability in Pesos as a currency. Even most Mexicans would, at this point in time, refuse to have thier wages and salaries paid in Bitcoins.