Thank you for your reply.
Okay, first off, you need to file a written appeal to the STD insurance
company and attach correct copies of your medical paperwork showing the correct dates. If they deny you again, you have to file suit against them in court for breach of contract
to get your insurance benefits.
Second, actually, you have a claim here against Chase potentially for "negligent hiring practices" which have now caused you intentional injury of infliction of emotional distress. Because this was caused by the intentional tort
of the employee, it is something that is exempt from workers compensation
(which is a good thing) and that means that instead of bringing a claim against the employer under workers compensation and only being entitled to pay for medical expenses and time missed from work, you can sue Chase and the employee in "tort" and that means you can get medical payments, lost wages, PLUS pain and suffering/emotional distress damages against them.
So you really need to consider obtaining a local attorney at this point and pursuing a suit against the employer as well as against the STD insurer if they deny your appeal with the corrected medical documents attached.