Most good mixers will have the ability to do a stereo line level input somewhere. It is a common thing. I wouldn't worry about running it in mono.

At worst, you could take two channels on the mixer, and pan one full left and the other full right. Assuming that you had the proper plugs and adapters.

I've heard that ground loops tend to crop up a lot easier when plugging an empeg into a mixer, so be prepared to have to deal with that. Which AC adapter do you have?