Although many adjectives fall before the nouns they modify, [...], those used in sentences or clauses with linking verbs fall after the nouns they modify. Linking verbs describe a state of being rather than an action; the most common linking verb is to be, and others include sense verbs like appear, seem, look, smell, sound, and taste.
Cynthia is fatigued.
- grammarly blog
Yes, the 'position' of an adjective can be used to determine the noun it applies to, but no, it doesn't help resolve the ambiguity you point out. In your example, the position of "drunk" in relation to the linking verb "was" tells you that it applies to the (pro)noun "she", which happens to be ambiguous here.
For example, if you replaced "she" with "the dog", then it's "the dog" that is said to be drunk. The ambiguity about who the original quote calls drunk comes from not pinning "she" down - "she" could refer to either of the previously mentioned people, or even to someone else. The ambiguity is not due to the 'position' of the word "drunk".