Who is referred as "Employer"- some senior management personnel or Director/MD/Promoter/Prop.? If it is some senior management personnel, "XYZ" can report to good offices of his/her appointing authority, MD, Head-HR, Company Secretary by letter/email under acknowledgment and demand exemplary punishment. Good companies have grievance redressal mechanism and the complaint and its findings shall become part of the personnel file of the employer/employee who has caused abuse at workplace.
If "XYZ" is a female she can rake up even severe clauses like leud comments affecting modesty, Istri Sabha, Women Commission.....
If "XYZ" belongs to category of scheduled tribes........he/she can invoke the law accordingly.
If "XYZ" is determined and has a strong resolve he/she can lodge criminal case, police complaint, complaint with O/o Labor Commissioner, labor ministry, NHRC, media, trade unions, local minister for company affairs, registrar of companies an demand...to cancel the registration of the company.
XYZ should bring a crowd and let this employer/employee find everyone and anyone breathing down their neck.
E mail is a written record. XYZ should forward this email to personal email id.
This is serious matter and offender employer/employee does not deserve to be pardoned. If "XYZ" is strong willed he/she can bring this employer/employee to their knees.