Hi Dan…
hmmmm…..
if you keep the bad quality video online…
bring in the better quality video…
put them both in a new sequence:
V2 = better video
V1 = bad video
align v2 clip so that it visually corrects the timecode offset
you can use the timeline panel menu to access the start time of this layered sequence so that it matches the timecode of bad video if necessary)

load this layered sequence into your source viewer
in your destination timeline (a safe copy) where you will be replacing the bad quality edits
disable the first icon: “insert and overwrite as nests or individual clips” so that it appears white.

now you should be able to patch V2 (the good quality video) to sequence track V1

the info tab should give you some timecode info about that bad video timecode (which should match the timecode in the source viewer since you changed the start time as above) to help you find it to match it in your source viewer (which contains the layered sequence)
you can use the X (mark clip — fcp shortcut) to set the duration of the edit in the sequence…
find the matching in or out video in the source viewer (and mark it with I or O accordingly)
then do an overwrite edit to lay the V2 (good video) in as the replacement to the bad video on V1 of your destination sequence.
nothing else should be patched in the sequence (unless you need audio too)…
but that’s about the best process I can think of to do it….
hope that helps!
Alex Udell
Editing, Motion Graphics, and Visual FX
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