To clarify
The tools are actually stones that indicate chip marks that might have been the result of using one stone to strike the intended “tool stone” and knock chips away.
The “tool stones” were found at a depth, in a certain location where some belief of what the earthen layers represent, may indicate that 2 to 3 million years passed, before the discovery.
The age of anything in the story, is not apparently determined by carbon-dating.
The fact that volcanic and earthquake activity, in addition to weather storms plus erosion, will alter layers of earth causing un-expected order, is also not mentioned.
Carbon dating only works for organic molecules and can only date accurately to about 50,000 years ago.
The discovered tools were found in the East African Rift area in the northeast region of the African continent.
There have been perhaps 100 or more parts of the African Rift that have been dated since 1970, including the famous Lucy fossils.
It is always possible that the dating is wrong - but, it is NOT just a one time measurement of an area that has never been analyzed before.
In my town in the PNW they were making a park on the river and discovered the earliest known tools in the area - dating to about 10,000 years ago or so. Shortly after the land bridge.
Yeah - the photos showed what anyone else would call a rock - but there were slight tell-tale signs on them. Pretty cool to walk along the river and think about humans fishing, foraging, etc. that long ago.