Very good advice from Timothy above.
I would also give two more tips:
1) sometimes an AAF will work better than an XML, and you can try that and see what happens. When I see issues like this, generally it happens because the camera was a non-timecode source (like a DSLR) or it's a camera that did not have a timecode lockbox for time-of-day timecode.
2) MixingLight.com did a very good series of Insights on conform issues some months back, and they presented a couple of hours on different very complex situations where things can go horribly wrong, along with some solutions.
Note that in general, you would run into trouble if you tried to conform this in Avid or FCPX as well, so it's not necessarily a Resolve problem per se. A lot hinges on file names, reel names, and timecode. If those three things are absolutely unique, you'll never have a problem. I have had some very complex conforms go smoothly to the point where the only thing that didn't come in was VFX and graphics, and those are generally a case-by-case basis anyway.
BTW, I would strongly advise you for a feature to break the show down to 20-minute reels, because it's much easier to conform 6 x 20-minute reels than a single 120-minute timeline. Once the reels are each conformed in Resolve, color correct them, then at the very end, create a nested timeline made up of Reels 1-6 and you'll have the complete film as one file.
I also generally ask the editor to give me a low-quality reference copy of the show with source file name & timecode at the top and record timecode at the bottom, so that in case I get lost (which sometimes happens even with the best of edit lists), I know what clip is missing and what the start frame should be.