Where and How are the legendary characters during Rime of the Frostmaiden?

I’m DMing ROTF for players that have a very deep knowledge of the lore of the Forgotten Realms, it doesn’t bother me at all, but I would like at least to be prepared enough anyway to properly address the campaign theme. I’ve read "The Crystal Shard", and keep digging into wiki and other sources of lore, but there is still a lot of things that I don’t know for sure.

Massive spoiler for the Forgotten Realms books or some other campaign books.

About Bruenor, Catti-Brie & Regis:

About Drizzt:

About the Dwarf, and more specifically the Battlehammer clan?

Overall do you have any advice on how to proceed with lore accuracy in the campaign, and some sources of lore I could read in preparation

What is the year in Dale Reckoning for Rime of the Frostmaiden?

Various internet sources claim to set the new Icewind Dale adventure at 1450s Dale Reckoning time.

Spoiler alert?

The entry for Auril in appendix C states that she could not stay away for long after the Sundering. It does not say Second Sundering, but I assume it’s not referring to the first.

Assuming a few years past before Auril returned, I’m assuming the intended setting for this is approximately 1491 DR. Which would make sense because that’s close to the reset-button epoch for 5E.

I’m just trying to clarify this point for some of my players because it matters which gods might be hanging around. I know I have liberty as a DM, and it was probably intentionally left vague. I was just curious what the community thought because it’s not super clear from my research and there seems to be disagreement. Can somebody line this up with the novels’ chronology? Thanks!