One thing you could try it's goto /system/app, delete/rename (i.e.camera.apk.backup) the camera apk, copy/paste the new one over, chmod the new one, then try to run it... (no guarantees, just an idea)
here's a link for the Xperia play phone.apk, it's pretty much stock dialer
http://db.tt/g4DvHAfN
Try the same as above, it might work...
The xperia play does come stock with vvm, but after I installed google voice, and told my phone to use that instead out vvm, it does dial google voice (I think... I've never called google voice to get my voicemail, I just use the android app, but it didn't sound like verizon's voicemail system)