Really not worth it the only time that a second set of servers would be needed is after a massive disaster like now and u rly can't except a company to rent a second space and train staff to maintian them for a situation that really is once in a 40-100 years situation where a disaster cripples the entire country.

As for it fixing
lag :nope servers would still need to commucate between each other + lag is more a isp issue anyway.
backup: As the reason above it's just better to have backup on site
To stop Maintance : if they could do this they would of done so already at the same site they have the normal servers there is definty more too it than i know anyway.