the Americans with Disabilities Act (ADA), employers are required to keep employees’ medical... with Disabilities Act") on the EEOC official website mentions medical examinations and medical inquiries... examinations must be kept confidential. ADA-covered employers may ask such employees

of a HIPAA or ADA violation

You have an ADA obligation but, also, if FMLA applies to your Company, it sounds like the EE's condition is qualified. You will need to look at both, which means transfer is a last resort, especially until you get this completely straightened out in terms of responsibilities under both laws

specific location, including contract and temp workers? At the very least, it's time to enter into an ADA