He was not terminated.
He resigned. By extracting resignation the VP has escaped from procedural hassles and has done away the need to conduct a fair inquiry, and provide opportunity of natural justice.
If witnesses were willing to testify then employee could have withdrawn the resignation immediately citing it extracted by force, coercion, intimidation, pressure.................
He was forced to resign. This can be termed as offence.
Forced resignation can be termed as deemed termination. The onus to prove may fall on affected employee.
If the evidence and witnesses are unshakable the employee may proceed further under the expert guidance of a competent and experienced labor consultant/service lawyer.
If resignation was extracted in Dec13 then what communications are on record till now?
The lawyer may look into the matter documents on record, evidence, and opine on merits.