Really we would need to give someone like you a full medical history work-up. Cauda Equina syndrome can of course give continence issues but so can a prostate issue and other things.

If the Wikipedia reference-linkMRI is clear for any direct nerve root or cord compromise then people need to look else where. Many of you symptoms could be explained from the disc or intervertebral structures themselves albeit for the weakness (if it is true weakness and not just pain provoked weakness or loss of sensation). Seems like you have enough people involved right now so I wouldn't keep shopping. Let us know how you get on and over time perhaps we can add some commentary.