Update:
Blackmagic Design responded to my support question about this, and suggested I try uninstalling both QT & Resolve, then reinstall Resolve 11.3.1, allowing it to use its own QT installer.
Still nothing. It will consolidate ProRes only when I opt to copy the ENTIRE clip, as opposed to trimming with handles. I’ve communicated this result back to tech support, but haven’t had a response yet.
Adobe Premiere CS 5.5 can, under Windows 7, trim ProRes and consolidate a project.
Wondering why Resolve can’t do this, as well?