AE Gamma shift issues

Hey folks,

I'm working in After Effects on test footage for removing wires.  I'm running into what I think are typical color workflow issues, where the gamma seems to be be interpreted differently.  This footage isn't critical, but it seems like a good opportunity to make sure I understand how to handle color in AE.  This may be a little long, but bear with me.

The camera used was a Canon 5D IV, using a standard picture profile.  The footage is dark, as the scene will be candle lit (though this is still a bit under exposed).  I'm not exactly sure what color space the 5D uses, but I believe it's Rec 709.  The picture profile is set to standard.  I'm working on an iMac Pro (2017) and the build in 5K display.

I've attached 4 screen shots to illustrate what I'm seeing:

1. The original file as viewed in QuickTime player (which I believe is using gamma 1.96)
2. The file in AE with color management disabled
3. The file in AE with color management enabled (and "use display color management" enabled, output simulation disabled)
4. The original file viewed in the Screen app, with custom settings of Rec 709 and 2.4 Gamma

Here's the main problem - If I leave color management off, put this clip into a composition and render it out to ProRes 422, the darker gamma is burned into the export.  If I try to use less contrast via Lumetri, the little detail you see in the Quick Time screenshot have already been lost, and can't be recovered.

So I guess my two questions are:

1. With color management disabled, why are the darker values written on export?  Is this a export format issue?  Or something else?
2. Using a color managed workflow, is there a way to retain some of the details you can see in the quicktime player screenshot?

Thanks for reading this far, and any insight would be greatly appreciated!

Cheers,

Bill