Here is the sentence:
Very impressive! You recognized that too many words separate the modifier from its target. In high heels, a prepositional phrase, is currently describing Billy, the bulldog, when its target should be Tonya.
To fix the problem, you should revise the sentence like this: Tonya made the mistake of walking her boisterous bulldog Billy while she was wearing high heels. Now we're sure which creature has on the inappropriate shoes!