@lsingh,
From the limited interaction in the thread it can be construed that: You have proceeded methodically, to defend your interest.
Proceed further and defend your interest without any affect and loss to you.
In the process if these HR people get grilled let them be…………
In your future transactions remain amiable but alert………….
If you can you may record reference of your final email to good offices on the document and you must take copy on the spot……………
------“I wasn't informed about the policy during my whole tenure in the organization till resignation.”
Rephrase or add so as to achieve pointed confirmation that such a term or condition or policy or rules was never kept in knowledge domain of employee e.g. …………….. is neither stated in job advertisement, interview call letter, selection letter, offer letter, appointment letter, HR/exit/severance policy or service rules kept by company at Employee/HR portal @ intranet of the company ( however you must download these documents and keep a soft/hard copy).
It is a known fact that gossip or rumor can not be rule or policy.
But before it is claimed the evidence should be in the custody of employee.
Leave no room for employer to dazzle you.
--------“Moreover, when I escalated ………………………”
Escalate to good offices of your appointing authority, MD, Chairman, Company Secretary…………
The personnel to whom you have been escalating are not your employer.
These persons simply want you to approach court of law if they proceed against you and be dumped in courts of law without any liability and effect on their job, employability, career, coziness of the office……………….
If the situation arises for you due to a situation created by them you should succeed in charging them by name and bring them out of coziness of their office and burn fire below their seats and give them blisters……………..
They should bear the monetary and legal cost like you.
-------“if these emails are enough to prove that they have forced me to agree to the terms they are putting up after my resignation,’
These should suffice if you have drafted these and covered everything as posted by you.
If you can manage to record (audio/visual) then it shall be superb and if required an employee may succeed in ridding the society from one adamant/recalcitrant/ bad HR personnel………
Wish you the very best.