How much ult charge is gained from biotic grenade and to who? (Ana + another healer)

Ana uses biotic grenade on a target (which heals 100HP), the secondary healer (let's say Mercy) heals them for a further 100HP (doubled by biotic to 200HP).

Which scenario is true?

1) Ana gets ult charge for 100HP healed, Mercy gets ult charge for 100HP (The biotic heal boost doesn't affect ult charge)

2) Ana gets ult charge for 100HP healed, Mercy gets ult charge for 200HP (The biotic heal boost enhances Mercy's ult charge rate)

3) Ana gets ult charge for 200HP healed, Mercy gets ult charge for 100HP (The biotic heal boost is attributed to Ana, and so enhances her ult charge rate)

I feel like it should be number 2, right?

Solution 1:

In your case it's scenario number 2, yes. The increased heal from the Biotic Grenade is credited to whoever is doing the healing.