Can Cramps In The Legs Be Due To Conversion Disorder?

Hello! Another undiagnosed neurological condition: 5 months ago my husband developed excruciating cramps in his legs. A couple of the days after the ER visit (he was given morphodone & valium injections), his gait became abnormal - to the point that now he's in a wheelchair. He has since developed tremors on the right side of his body, muscle spasms in his back, tingling in his legs, cognitive impairment, bladder / bowel issues, sweats only from his head, vision issues & has no sense of balance. He fell backwards in his chair about 2 months ago & since then his neck pops, cracks, is debilitatingly painful, & he's now unable to move his head. He's had MRIs, x-rays, CTScans, bloodwork, EMG, 2 LPs, Lyme test, urinalysis. Next week he gets SSEPs. We've now seen 3 neurologists, 2 neurosurgeons & a physiatrist (both for his neck) & everything has come back clear. At the moment the diagnosis is Conversion Disorder but we are sure that's not the case. Can you lend any advice?