I find the way fogBugz shows reassignment of a bug really unintuitive.
Personally, I think the current set up works. Haven't had the chance to look at the code, but it should be easy enough for you to just edit the page and swap the 2 variables and make a minor grammar change.
And your 'improvement' is ungramatickal.
I actually think that it is a good thing to first see to whom a case is assigned as this is the more important information in my view
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