The BLED112 by default supports up to 3 simultaneous connections. The python API supports this as well – you should be able to read from two Mooshimeters without a problem.
Bluetooth Low Energy does not have a good interface for triggering simultaneous events. If you want to get the meters as close as possible to triggering at the same time, after connecting to them you can pause them both and tell them to resume sampling at the same time. That should get your meters sampling within a few milliseconds.
Hope this helps!