1. It is good that you have analysed the issue properly.
2. HR is not our employer. It is just another employee like you. Therefore you need to escalate to good offices fo appointing authority,MD,Chairman, in writing under proper acknowledgment. This is personal matter and can be sent from personal email id also. Download the printouts of our query and reply and forward to your email id.
3. There are some unwritten policies (at least for employee e.g. you) that won't be supplied to you by HR, although it might be a policy by employer for HR to decline as in your case.
4. It might be possible that HR has framed such policy and/or is a stakeholder and hence HR due to its helplessness or fear of reprimand by employer may not provide any relief to you.
Hence beyond a point do notre,ain entangled with HR.
You may send you gentle reply to HR as posted in your query and demasnd reply. Let HR decline to you.
5. Leave entitlement is matter of facts as per enactments applicable to establishment/employer/employee e.g. Shops & Estbs Act. You may carefully go thru the enactments and leave policy of the company.
Leave is counted in attendance i.e. paid days.Approved leave is part of service period.
Employer can not keep less than prescribed in enactments but can keep more than it.
6. What is issued to you; offer letter or appointment letter?
Is it mentioned in offer letter or appointment letter that service conditions shall be governed by HR policy/service rules and regulations/standing orders (certified/model)?
Do you have copies of these?
7. If the reason for declinature is outside the policies already communicated to you, then yu have a valid claim. However as suggested above let HR or even good offices decline again quoting and attaching the concerned policies.
8. Since you are not satisfied you may firm up next venture ASAP.
You may decline to accept the FnF statement/settlement if it is not satisfactory and not correct.
9. Your escalations and regular follow up may not be viewed positively.
Hence move on!