As Drang begins to advance, the gnome vocally interrupts him. "I can't let you distract any of my workers, but I am willing to give you a tour of the site to prevent that from happening. Come down into the crater without talking to anybody else and I'll let you properly appreciate what we discovered."
Neither the workers nor the gone react to Melhved's comment.
Spoiler: For those who make a DC 29 Insight check
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What he's saying is partly true, but even the true parts have an ulterior motive behind his decision to say it. He doesn't want his workers distracted, but isn't willing to give out a tour. He wants to draw you into the crater, but not for the reason he said.
He wasn't able to overhear or translate Melhved's comment.