Hello and welcome. I am so sorry to hear about your mother's condition and the difficulties you are having with your employer.
If the FMLA does not apply to your employment, then no law protects you and your employer is free to terminate you if you do not return to work as they are demanding. That is the unfortunate truth regarding your situation. Therefore, the only avenue of recourse would be to argue that the FMLA does in fact apply because the company you work for is really part of the larger company, which does have more than 50 employees. Keep in mind, though, that no matter what the requirement is that more than 50 employees work within a 75 mile radius of your place of employment--the size of the company alone is not what controls.
But if the larger company has more than 50 employees working within a 75 mile radius of your employment, and if you can argue that the large company and smaller company are "joint employers" (meaning they are jointly owned and controlled and for all intents and purposes the same entity), then the FMLA may protect you. If that is the case, then your employer would be breaking the law by firing you without affording the protections required by the FMLA.
If you think you can make the argument that the two companies are "joint employers," and if them being joint employers would mean that you have 50 employees working in a 75 miles radius of your employment, then the next prudent step would be to retain a local attorney to write a letter advising your employer of their FMLA responsibility and threatening a lawsuit if they let you go. Most employers are relatively litigation averse, and so any plausible threat of a lawsuit will probably be enough to get them to re-evaluate their position.
This is really your only hope of keeping your job short of complying with your employer's request to return to work. Otherwise, if you are fired your recourse is to file a lawsuit for wrongful termination
in violation of the FMLA, making the arguments described above. The law does not afford any other legal protection to individuals in your circumstance, I'm afraid to say.
See here to locate a lawyer in your area who can write the demand letter to your employer: http://lawyers.findlaw.com/lawyer/practicestate/employment-law-employee/arizona
I hope that you find this information helpful. Please do not hesitate
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