Allworx Phones with Asterisk

I have a whole bunch of Allworx phones that we’ve been using with an Allworx system. However, I’m considering switching to using Asterisk.

I emailed Allworx and they claim that Allworx phones won’t work with Asterisk. However, I’m thinking that they may be trying to deter me from using Asterisk, and that there may be a way to get it working.

I have done google searches on the issue and have came up with relatively limited information. Does anyone have much knowledge on this particular issue? Any insight would be appreciated.