What is the reason for scripture not telling us who provided the authorization, was hiding that information important or was it just a minor detail.
3 reasons:
Scripture is written for instruction in righteousness and knowledge of the Lord.
Scripture records what is necessary for that purpose.
Scripture also demand study, and doesn't spoon feed the readers as babes.
Scripture also lays snares for the fault-finders, such as what's not written must presume error.
And so, in this case, the record that Saul did have authority in Damascus from the high priest in Jerusalem, invites historical study of Roman Imperial rule over the provinces.
Among political rhetorics and poets, not the serious historians. They exercised choice of sources, but they did not skew the facts for advantage. Herodotus did not change facts to promote Hellenism over Asian culture. Livy was not writing an Aeneid for Imperial legitimacy of the Gods.What was Luke trying to say in Acts, as in the 1st century, the message of history was far more important than the actual facts, facts could be distorted to deliver the message, and no one would have objected.
Your revisionist assumptions of falsifying records are based upon purposed presumptions of lying recorder. Not by the facts.