To be commercially endorsed for Advanced you need to complete the Advanced CoC exam, not the 2 day Advanced course. The course is there as training should you need it (which most people would, if nothing else to ensure you have had a chance to practice under guidance the sort of things the examiner could ask you to do and adjust skills as needed). Worth speaking to your chosen centre to see how they arrange - some will facilitate an exam immediately after the course, others might have a gap between and arrange the exa separately.
Yachtmaster Coastal - you don't necessarily have to have the paper certificate but "training to that level" however you choose to do that. The course is highly recommended though to ensure you've fully understood and practiced everything. As long as you are familiar and confident with all aspects of the YM Coastal shorebased syllabus to either talk about or put into practice, that's what they will be looking for.
Miles/hours logged - whether it's actually written down in a log book or you verbally describe your experience, it's pretty obvious whether you've got the required knowledge/experience or not. The sea time/mileage requirements are there for a reason, to make sure you have sufficient experience to give a good chance of succeeding with the CoC exam. Presumably if you're a full time speedboat captain using your Level 2 you have plenty of days/miles as skipper, but in a very specific area and not at night?
Night driving - you definitely need some night experience, as during the course and/or CoC exam they will be asking you to take command of the boat at night time, plan and execute a passage, find unlit points in the dark, etc., so you need to be familiar with all those techniques and very confident in your ability to drive/navigate in the dark, potentially in unfamiliar waters. Clearly on a 2 day course you'll get a single night driving exercise at the end of the first day, so if that's the only ever time you've helmed a boat at night and done planing speed navigation in the dark, chances are you will need much more practice before the exam.
Best bet is to call your chosen RYA centre where you think you will do the course and/or exam, and they will generally very happily talk to you about the requirements and work with you to make sure you are ready.
There's also various videos on YouTube with examiners explaining what is required, e.g.:
