My advice is similar to daveornee's; take the wheel to a competent
wheel builder or follow the recipe in any number of the books on the
subject; retension, redish and stress-relieve the wheel yourself.
That 1/4" difference indicates that the wheel is mis-dished by about
3mm, which is just enough, in my experience, to make a road bike
misbehave in the manner you describe.

I doubt that the wheel is beyond saving.
--
Typoes are a feature, not a bug.
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