Now that I've flown this route, I can give some updates!

The primeclass lounge did let me in, and for 9 hours (seemingly swiping priority pass 3 times). The private rooms are fantastic with a nice view and a good bed! Worth noting there is an airside aerotel that seems nice as well!

As for the first class lounge, they definitely did a double take when they saw my 20+ hour layover and had to call someone over after letting me into the first class lounge! But for as long I as there, they were keeping it staffed!

On the first day, I essentially had an attendant to myself, which was an absolutely fantastic experience. Some of the best food I've ever had, and I don't say that lightly (menu not as varied as EK/EY first lounges but the food quality is easily on par with Michelin-star restaurant food). Hands down the best lounge I've ever been to, easily better than EK/EY first lounge.

downsides: no $300+ bottles of alc in lounge (that others have reported earlier, probably between alc shipments), the amenity kit was lacking any Amouage fragrances, and when asked they said it was due to "covid" (when I asked another they admitted it was just temporarily out of stock). Overall lack of consistency seems to be their downside.