You ended up working it out, so I don't need to tell you how to pronounce it.
Your finger placement looks good to me. And I'm pretty sure I couldn't do 5.23 to a metronome in triplets, so that was an absolutely awesome idea I'll have to work on.
5.23 is a real bastard to do. Most have trouble with it. I liked watching you stop when you flubbed it up and start again. That little move will make a huge improvement in your skill once you get it down.
The only thing I would have recommended is what you did; slow the metronome and work on it at a slower speed. At 60 bpm in triplets you're doing 180 bpm with 5.23, so the fact you could do it as well as you did shows how much practice you've put in. Keep it up!
P.S.: Thanks for the thanks. I decided right before Christmas that I want to do as much as I can to promote a community here, so that feedback is nice to here.