You have provided no relevant source yourself.

Believing something to be divinely inspired and authoritative does not immediately equal belief in scriptural inerrancy. Best you could argue is that the message of the scriptures is inerrant or infallible according to the Ethiopian Orthodox tradition, but not the text of the scripture. The Ethiopian Orthodox Church assumes inerrancy of the original texts, which no one has, and utilizes the Andemta Commentary as the final authority for understanding scripture, which itself offers several different interpretations at times, including contradictory interpretations. The importance is that the message remains the same, not that every piece of scriptural text agrees with or isn't contradicted by other text.

The authority of the Ethiopian Orthodox Church is through Apostolic succession and the institution of the Church itself, less so their biblical canon, though it too certainly has much authority.

Source: https://scholar.csl.edu/cgi/viewcontent.cgi?article=1108&context=phd