The main source of water in the mountains is precipitation. It forms snow cover, snow caps, and glaciers, which melt at positive temperatures and create streams and lakes of various sizes.

Unconvincing. Look at the plateau's area. Estimate the waterfalls' flow rate. Evaluate the water balance and realize you've made a mistake.

Where do you have information about the plateau and other features of the territory? A link to a video hosting service is, of course, a good thing. But it would be nice, of course, to add text information (it is not always possible to go to another resource and watch a video). Of course, if there are local natural and climatic features, then there may be its own specifics of the water balance. But all other things being equal, precipitation is the main source of water in the mountains.

The aquifer is geologically inserted at the boundary zone of the mountain.

The discussion has begun. This is important.

In Africa there is the Ethiopian Highlands, which is the source of the Nile River. The Nile River is the longest river after the Amazon. The Nile flows through the desert and therefore has no tributaries. The Nile floods in August, that is, during the peak of evaporation from its surface.

The question is, is all this provided by the precipitation on the Ethiopian Highlands?

Note: On the way through the Sahara Desert, the amount of water in the Nile River increases.

Mah from https://naurok.com.ua/prezentaciya-vodi-suhodolu-afriki-222952.html

It is snowflake capped mountains and cloud precipitation cycle in my opinion.

In mountainous areas, there are two types of precipitation: rain, which rarely occurs and which when it falls forms a runoff, or some of it seeps into the ground and is stored there and then appears in the form of water springs. The second type of precipitation is snow, which falls and remains frozen on the slopes and peaks of mountains for long periods. When the air temperature in contact with it rises to about 15 degrees Celsius above zero, this snow begins to gradually melt, forming channels and rivers.

Eau de montagne est constituée principalement des précipitations (eau de surface) sans oublier les eaux geothermales eau de cristallisation) dans le domaine magmatique.

Water, sometimes frozen, falls out of the sky, just like it does everywhere else.