If you’re making Avid media in Resolve, you absolutely need to assign a REEL as that is what gets embedded into the MediaFile as “Tape” and will be used for relink, lists, dupe detection, etc. This is a fundamental error done by users with little to no experience in the post process compounded by the fact that there are videos showing you how to do it wrong… grrrrr.
The fact that is shot 4K or 1080 has no bearing on the REEL and conform process. Proper REEL assignment is essential regardless of resolution. If you are in 8.3 for example, you might consider making 4K compressed dailies and work in 1080 to have FrameFlex capabilities etc. But those workflows also take planning.
Make sure you have REEL assigned. If you want to mimic what Media Composer does, then make sure “assist conform” is set to using clip’s file name.
As far as audio is concerned, you can sync via the timeline as you mention, then subclip each segment out and AutoSync those, or just mark the source clips with a Mark IN and sync two at a time with AutoSync, or if they have common timecode, just select all video and audio clips and use AytoSync. If you use PluralEyes (even their free 30 day trial) then refer to my blog on the topic:
https://24p.com/wordpress/?p=218
Michael