The situation you describe would be biamping with an active crossover. The only problem is you really know nothing about this speaker, in regards to crossover points, slopes or other filters. Hooking up a simple straight in bi-amped system may sound better because there won't be any poor quality caps, coils or resistors to pass through. It may sound worse because you may not be able to set it properly, and there may be other filters on the crossover that you don't know about.

My first instinct is to try and fix the crossover or order a replacement. If you want to try the bi-amped system, you pretty much already have what you need to try it out. You have one amp and an active crossover, and you could probably borrow a second amplifier. Try it out, see how it sounds.

Adam