You're welcome
Both variants are used (and seen in ancient writings), Zal-moxis and Za-molxis, but historians consider the variant Zal-moxis as probably the correct one, based on an inscription about a Getae-Dacian king from today Dobrogea area (aka Scythia Minor at some point) called there as Zalmodegikos.
So is considered that names with root Zal were used and this is the correct variant.
Possible Zamolxis to exist too, who knows, surely Greeks adapted foreign names to their writing and pronounciation and is not sure how correct they were.