I’m sorry, I don’t quite understand. Do you mean the damage he takes from bleeding doesn’t count towards the True Form’s buff?
I meant a slightly different thing — bleeding might no longer be credited as a damage source from a particular mercenary, like it used to be, if I recall correctly: namely, there would be several status effects or enchantments on a bleeding merc, each attributed to a particular ability applying it, and now it just stacks.
The first phase is ‘Unimpressed Nefarius’ and four lackeys, so only one space left, if we assume 6 to be the maximum (which isn’t always the case, as I’ve reported here, but usually it is), thus only the first ‘add’ from the second phase summoned — makes perfect sense! 
Speaking of slots on the board, reminded me of another matter: what do you think about that one with the C’Thun bounty, should we consider it a bug or a design limitation?
A few other notes about some bounties (difficulty on which it was tested in brackets):
Lokholar (Heroic): his ‘Avalanche’ ability (Attack a random enemy. Repeat for each of your other characters.) seems to respect taunt now. I don’t rightly remember, was it always the case or was it fixed at some point?
Garrosh (Normal) has a text like this: ‘Restore 25 health to this Merc after another character casts a Shadow ability.’ However, this seems to trigger only from the abilities of his allies, not enemies — in particular, the player’s Twilight Extinction or Shadowflame would not heal him.
About a few abilities:
– The full animation for Varian’s Retaliation is visible only for an enemy Varian, not mine, where it just shines a lot (on PC, Windows).
– Don’t know if this is a bug or a proper interaction, but an interesting one: if a merc (it was an enemy Uther in PvE in my case) would cast a Holy ability twice due to Velen’s Blessing, but is killed after the first cast (my Trigore did it), then the second cast woudn’t happen, despite the text: ‘Your next Holy ability casts twice.’
That might be another example for the subject of dying mercs casting their abilities or not, as with Trigore and Long’xin, which we discussed a while ago.