Are the errors in question wirting errors or type setting errors?
Errors are errors. If there were errors, and there were in the 1611, that’s all the proof I need to aver the KJV is not inspired.
To your question about proof..
Definition of proof
a : the cogency of evidence that compels acceptance by the mind of a truth or a fact
b : the process or an instance of establishing the validity of a statement especially by derivation from other statements in accordance with principles of reasoning