Dodgy Applecare rejection

I had this very "interesting" encounter from Apple recently.

I purchased an Applecare warranty from Ebay from a very reputable seller.The seller provided me with all the details and pictures such as the serial number,box reference number,an invoice etc.

I called Apple to get my warranty registered and they said there were some issues and requested the pictures of the box as proof of purchase and did whatever they requested of me.

I submitted it to them and in about 4 days they called me to get mention that the warranty was rejected because it was not from an Apple authorized re-seller.

Does it need to be an authorized re-seller from your country? Okay sure whatever.Let's say Apple can reject whoever the **** they want.

Next,the guy on the phone kept requesting I get their "Official" Applecare warranty.He asked me to do that about 2-3x.I said I don't want to right now and hung up unhappily.

I sent an email to that guy so that I could attain an email confirmation about my rejection.I guess I wanted some proof I can send to Ebay and the re-seller.

The guy I spoke to just sent me a generic email with my Case ID asking me to call Apple again to raise this issue.Again.

So I do that,I call Apple up again and I speak to their Agreements team (AGAIN) and she states the same thing.Can't register the Applecare because it is not from an authorized Apple re-seller.I tell her,I just want an email confirmation telling me my serial was rejected?Is that really so hard.

Turns out it is very hard.She says they cannot help me.They cannot send me any rejection notice or any such document.Interesting.

SO here I am after repeated calls to Apple and dealing with their ridiculously unhelpful team because there is no complaints department or escalation.

Here are my questions:
1) Can Apple reject my warranty?Is it legal after I've provided all supporting evidence because it's not an authorized re-seller?

2) Is purchasing an Applecare warranty only valid if I purchase it from an authorized re-seller?Where is that condition stated legally?

3) Is it Apple policy to just tell me on a phone with no evidence whatsoever that my key is rejected?Is there solid,written proof?
4) What is so hard with sending a simple notification that my code has been rejected and to contact the supplier for a refund because it's not acceptable?

This is my first Macbook Air purchase ever.It's been a disgusting experience for me and I am unsure if I'll ever buy any Apple product again.I am unsure what other steps I can take and have thus resorted to airing my frustrations on this forum.Is there no manager or legal that can confirm or reject this because it sounds really dodgy to me.