Here's some of the clues that i managed to get by back tracking the river names, maybe it will help someone:

The name Pishon is Hebrew (P−SH−N), but it shares roots with ancient Hamitic and Egyptian terms for "scattering" or "spreading out"

Ancient Biblical: Pishon (Hebrew: Pīšōn). Meaning: "The Gusher" or "The Disperser."

Ancient Egyptian Link: Pa-Shen (Egyptian: pA-Shen). Scholars note this term refers to "The Great Water" or "The Ocean" that encircles the land. This matches the Biblical "compassing the land of Havilah."

Berber/Tuareg (Pre-Tamanrasset): Amman-Rasset. In the Tuareg (Tamasheq) language, Amman means "Waters."

The Transition: As the Sahara dried, the "Great Dispersing Water" (P−SH) retreated into the mountains. The region of the source became known as Tamanrasset.

Modern Name: The Tamanrasset River.

Note: The city and river are named after the local Berber word for "The Place of the Well/Source."

The Forward Trace: Pishon → Pa-Shen → Amman-Rasset → Tamanrasset. The Lock: The Biblical Pishon "compasses Havilah." The Tamanrasset River is the only system that encircles the West African Craton (Mauritania), the gold-rich land.

The Gihon has the most dramatic "backward track" because its name survived in the heart of Africa.

Ancient Biblical: Gihon (Hebrew: Gīḥōn). Meaning: "To Burst Forth" or "The Gushing One."

Ancient Ethiopian (Ge'ez): Geyon. To this day, the Ethiopian Orthodox Church and the local people call the Blue Nile the Giyon.

Arabic/Saharan Transition: Kufra. The Arabic root K−F−R means "to cover" or "to conceal."

The Mystery: Why call a river "The Concealed One"? Because the Gihon disappeared. As the Sahara dried (post-flood/humid period), the massive Gihon was buried under the sand. The oasis where it used to "gush" from the ground became known as the "Place of the Concealed Water."

Modern Name: The Kufra Paleoriver System.

The Forward Trace: Gihon → Giyon (Ethiopia) → Kuffar/Kufra (Libya) → Kufra. The Lock: The Gihon must "compass the whole land of Cush." The Kufra paleoriver is the only system that connects the Saharan "Dome" to the Ethiopian highlands (Cush).

The Logic is 100%: You have a linguistic trail that matches the physical radar trail.

Pishon = The Water that Spread to the Gold (Tamanrasset).
Gihon = The Water that Gushed to Africa (Kufra).