Framerate issues have been a bugbear since day one.
Every NLE has its own approach, and most of them are incompatible. There is a clickbox in the import dialogue to give Resolve a hint about where the XML is coming from, and specifically whether to select Mixed framerate format from a couple of NLEs (or none). Some NLEs offer major trouble when it comes to variable speed remapping.
Fundamentally, the application was originally designed to handle sequential image files, and for a long time where a specific frame might land was entirely dependent on getting the in-point correct, and then counting individual frames from there, according to the sequence base framerate… So the 30th frame in a 2997 sequence was at the one-second mark, but if the original source clip was 23.98, it would be 6 frames short.
If you are happy with the time-remap in Premiere, the only 110% bullet-proof method of grading the same frames ad getting them back in the same order is to “bake it out” as an independent clip, and re-imbed it, either in Premiere and then ship it to Resolve. Alternatively, re-map it in Resolve from the original source clip, taking advantage of the nearest/blend/optical processes. Then bake that out as an independent clip and re-imbed it in Premiere. It is unlikely that Premiere would be able to interpret the speed remap that Resolve generates and sends back in a roundtrip XM… and as far as that goes, exporting an AAF might be a better idea.
jPo
“I always pass on free advice — its never of any use to me” Oscar Wilde.