Priority Date Porting - Pls advise

[rcmuskula]

I came to know thru a receptive USCIS call center person that USCIS has not been considering my previous priority date as my old 140 was revoked.
(I had my labor and 140 approved with another company in 2000 before I lost job in 2000-2002 recession). When I told her that I can use my 140 even if previous 140 was revoked as long as it was not revoked due to fraud or misrepresentation. She told and talked her Supervisor and came back with the same answer that I can’t use it.

After I put down the phone, I did research and found evidence supporting my claim in
Field Adjudicators Manual (Chapter 22). I took the details of the manual (Chapter, section, etc) and called back and luckily connected to the same person. She took the details and told me that she would check it first and then show it to her Supervisor.
She took my contact details and told me that she would call back after talking to Supervisor. She called me back after two days to inform me that I am right and her Supervisor agreed to that. However, as per her, her Supervisor now says that I can’t use my previous Priority Date as my old/previous Labor has been used/substituted for someone else by my previous employer.

I have been trying to find, since then, if there is any reference to what they said in any of the USCIS manuals in vain. To me, it seems that Superpvisor is hell bent on denying me to use the old PD. I suspect that because he/she said that I can’t use my previous PD because of 140 revocation first and when I proved that wrong, he/she brought this new reason that I can’s use it if the previous labor has been used/substituted for someone else.

I called USCIS again just now and connected the same person again (third time lucky).
I told her that I did research and find any reference anywhere on the web (including USCIS site) to what her Supervisor is saying now. She said she would talk her Supervisor again and send me a mail (postal).

I do not what to do, If she says that her Supervisor sticks his/her guns in the mail.
Is there any truth in what her Supervisor saying?
How do I prove that her Supervisor is wrong?
I took a InfoPass appointment for next Monday (3 hours drive from my place (:- )
and hoping for the best.