What is the correct damage for a Dragonclaw’s Scimitar?

I purchased the roll20 version of Hoard of the Dragon Queen a while ago. It includes all the monsters needed for the campaign. The roll20 version of the Dragonclaw has two attacks included:

  • Scimitar: +5 to hit, 1d6 slashing damage
  • Scimitar (Fanatical Advantage): +5 to hit, 3d6 slashing damage

I have been playing using these attacks for a while but I recently noticed that the D&D Beyond Dragonclaw actually has the Scimitar damage listed as (emphasis mine):

Scimitar. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) slashing damage.

I searched for HotDQ errata and this is not listed. I am leaning towards the D&D Beyond version being correct with the Scimitar being a finesse weapon and using DEX bonus for damage.

I don’t own a physical copy of the book. What is the correct damage for a Dragonclaw’s Scimitar attack?