My fiancée was recently diagnosed with degenerative disc disease and myofascial pain

As someone with a similar condition, I sympathize with your husband's situation.  In California, an employer with 5 or more employees is required to make reasonable accommodations for an employee's disability or chronic medical condition unless doing so would pose an undue hardship for the employer. The employer is also required to engage in an "interactive good faith process" to determine an appropriate accommodation, and a failure to engage in this process can, itself, be grounds for a lawsuit. The duty to engage is an ongoing duty as well, meaning the employer cannot just engage once and then wash their hands of the situation.  From what you described, it does not sound like the employer is engaging in an interactive, good faith process. Having said that, degenerative conditions are tricky because it is often difficult to prove that the condition is worsening because of a specific cause or just getting worse on its own.  You would need expert testimony to establish this.  What is a more likely scenario, I am sorry to say and having handled many cases like this, is that the employer ignores the doctor's light-duty orders, falsely claims undue hardship, and your husband then suffers a more frank, serious injury such as a fall, etc.  If your husband's employer has an employee manual, review it and see what it says about requesting accommodations.  Request accommodations in writing.  Get the specifics of what to ask for from the doctor, but don't just rely on the employer communicating with the doctor while you are left on the sidelines.  Be proactive.   If the employer refuses, does not offer reasonable alternatives, strings this along, contact an attorney in person right away who can advise you about filing a complaint with the Department of Fair Employment and Housing, obtaining a right to sue letter, and filing a civil action.  Here's a good website about the reasonable accommodation process in California.