Does Voidgate double the damage of blue Teemo, and how does Teemo's ability work with targeting multiple units and Deflect?

Ruling: Blue Teemo can choose up to 5 units when the ability triggers, and you pay Deflect costs at that time (only once per chosen unit). When you reveal cards with Hidden, you deal 1 damage for each Hidden card revealed, and you can distribute these individual damage instances among the chosen units however you want. Voidgate adds +1 to each individual damage instance.

Sequence:

• When Teemo's ability triggers, choose up to 5 target units
• Pay any Deflect costs for chosen units (once per unit)
• Reveal the top 5 cards of your library
• For each card with Hidden revealed, deal 1 damage (can be distributed among chosen units)
• Voidgate adds +1 to each individual damage instance (so each becomes 2 damage)
• Put revealed cards on bottom of library in random order

Nuances:

• The damage happens during Combat Showdown (before combat damage), so it can kill units before they deal damage
• There is no downside to choosing all 5 attacking units if none have Deflect
• This ruling is controversial - some judges disagree with the official interpretation and rule it only targets one unit and deals damage as a single chunk