While Heaphy was in the role of hawk-eyed, sure-handed, specimen-procuring guide, Hochstetter, Haast and their colleagues were delighted by him and quick to sing his praises. (source)
This sentence strikes me as missing an article. Since "guide" is a count noun, shouldn't the sentence read:
While Heaphy was in the role of a hawk-eyed, sure-handed, specimen-procuring guide, Hochstetter, Haast and their colleagues were delighted by him and quick to sing his praises.
Is "the role of guide" grammatical?