I don't know. There's no apology. Just a half assed explanation.
Taking my english skills, calling someone an indian cowboy, is saying indians (posers) trying to be cowboys (the real deal).
Literally, figuratively, metaphorically is definitely saying more than what it's not. And it's not positive.
Instead of discussing facts, @cloudgroupsys' small mindedness to discuss and expose their ignorance (and what likely shows in many other things) simply, cannot, be overlooked.
"Cowboy" is a term a developer often uses to describe someone who develops something without thinking it through properly, often fails to test, and ignores the consequences.
It's often used like this: "He's a real cowboy - he wrote a SQL query that he tested on his own machine and then deleted data when he deployed it to production".
You are correct - it is an insulting term in this context.)
You can argue if that apology was enough or if it was a full apology. But I feel like saying "he didn't apologize" is an oversimplification.