Odd indeed that D'vorah, who was lived in the area of Shevet Ephraim (just north of the area of Shevet Binyamin), should be buried so far north.

How was this kever identified as hers?

I do not know. I will ask Nava, the Devorah Haneviah expert, the comment...

Maybe Nava will come in and explai more, but if you follow the link in the post and go to the Q&A section, you will find the answer... click here to go directly to the Q&A

Rav Israel Meir Gabai Shlita has ORIGINAL documents from the ARIZAL of the exact location of KEVER DEVORAH HANEVIA, a'h.

And how did the Arizal come to that conclusion?

I do not remember the exact details (I will try to find out), but the Arizal used some sort of kabbalistic process to determine all the grave sites of the avos and gedolim in Israel and say which were authentic and which were not. I do nto know the process, but much of our knowledge in the area is based on the arizals determination.

Maybe someone knows more details..

If there's no mesorah and no definitive archeological or other proof, then I personally don't buy it.

That's just me. I would love to be proved wrong though.

Devorah HaNevia's, a'h, husband, Barak ben Avinoam, zs'l, lived in Kadesh (now known as Tel Kadesh) and was from shevet Naftali. In Kadesh Naftali, he served the talmidim of Yehoshua bin Nun, zs'l.

Devorah HaNevia (from shevet Efraim) lived in Bet El and judged Israel under the palm tree (Tomer Devorah).

After separation of 40 years from her husband, (prusha), she rejoined her husband in Kadesh and there, both were buried.

Sources:

Rabbi Menachem Perez HaChevroni, zs'l:
"I went to to Tel Kadesh in the Galil and I saw Kever Devorah HaNevia, and she is buried in the Galil"

רבי יצחק חילו, ה"א צ"ג Rabbi Yitzchak Chilo, zs'l:
"Kadesh is Kadesh Naftali as is written in the book of Judges 4. Very few Jews lived there, only to upkeep the holy graves of the Tzaddikim and welcome guest coming to pray. In the graves are buried Barak ben Avinoam and his wife, Devorah HaNevia"

Sefer, Igeret Yechus Avos:
"The city of Kadesh is Kadesh Naftali, the burial ground of Barak ben Avinoam and his wife, Devorah HaNevia"

Sefer, Yichus HaTzaddikim:
"In Kadesh are buried Barak ben Avinoam and Devorah"

Sefer, Igrat Yachasuta:
"Kadesh is the location of the Bet Midrash of Yehoshua bin Nun and nearby, are Devorah and Barak ben Avinom"

Sefer, Igrat HaKodesh, Zichron Yerushalayim:
"Kadesh is the burial place of Devorah and Barak".

Rav Moshe Yerushalmi, zs'l:
"In Kadesh, underneath the village are buried Devorah and Barak ben Avinoam and a large stone is placed on them"

Shavchei Yerushalayim:
"Kadesh is where Devorah and Barak are, and on top of them are large stones".

Tov Yerushalayim:
"Kadesh, in Arabic, Kadis, near לניאס, are the graves of Barak ben Avinoam and Devorah HaNevia... and on top them are etched large caves".

*****************************

Near the wellspring and the antique synagogue, which was called "Midrash Yehoshua bin Nun", the Jewish mausoleum (structure of upper burials) (in the Gemara, it is referred to as "Nefesh") where Devorah HaNevia, Barak ben Avinoam, and Yael, a'h, were buried in alcove graves, was intact.

But during the Six Day War, since the city of Kadesh is situated at the border of Lebanon, the city of Kadesh was bombed and the structure of the mausoleum was destroyed. The stones appear to be intact but the walls and the roof of the mausoleum fell.

According to drawings we have from the 1900's, it is possible to reconstruct the mausoleum and save the Tzaddikim's graves that are buried there in disgrace.

http://he.wikipedia.org/wiki/%D7%AA%D7%9C_%D7%A7%D7%93%D7%A9

and

קדש נפתלי היא עירו של ברק בן אבינעם.

קדש נפתלי נמצאת בגליל, בנחלת שבט נפתלי. זיהוי המקום אינו ודאי, אך יש המזהים את קדש נפתלי עם עיר המקלט קדש.

בקדש נפתלי קבורה דבורה הנביאה.

http://he.wikipedia.org/wiki/%D7%A7%D7%93%D7%A9_%D7%A0%D7%A4%D7%AA%D7%9C%D7%99

thanks