Could the earth be much older than the currently accepted number?
The age of the solar system is 4.6 billion years.  We know that because almost all meteorites are 4.6 billion years old¹.  Therefore, that puts a very solid upper boundary to the age of the Earth.

According to solar system models, it took between 10 million and 100 million years for the Earth to form in the early Solar System.  That result is consistent with the independently estimated age of the Earth of 4.54 billion years old.  The Earth could maybe be 10 million years older, but it certainly couldn't be older than the solar system.



None are older.  We've never found a meteorite from outside the solar system.  I expect some scientists would have given an arm and a leg for the opportunity to sample some rocks from interstellar Oumuamua but it was not possible.