Accommodating some situations can be challenging, and may require some out-of-the-box thinking to come up with customized solutions. Again, the threshold here requires that accommodations must be reasonable, but do not need to be perfect.
If an employee refuses all reasonable attempts at accommodation despite the employer’s best efforts, then the employer has met their duty. If the employee is still refusing to perform their working duties, or to attend work, that may then amount to insubordination, or they may be deemed to have abandoned their position. Consult an employment lawyer before making any firm decisions in these situations, and be sure to keep careful notes as to what attempts at accommodation have been made and the employee’s response each time.