Is what he said difficult to understand (genuine q)?

I thought the guy was pulling a classic "o shyt it's my turn and I was reading the Beano what did he say oh I'll pretend it was his fault"

The first few words were a bit tricky, but I got the gist, and certainly when he repeated it, it was perfectly intelligible.

I had to listen to it three times before I could figure out what he was saying. Why is it rude to politely ask someone to repeat what they’ve said if you don’t understand what they’ve said?

If you’re not expecting it, it takes a few syllables to get get into the rhythm of his accent, so you may miss the first part of the sentence, but it’s fine after that. 

Got the gist but it was too fast and mumbly. That would be a problem for public speaking regardless of accent.

Make an EFFORT 

Yes, that’s what that other chap in the video was doing. And that’s what I did listening to the bloody thing three times.