Do I need to summon the NPCs during the boss fight to complete their quest?

[Lactobacilos]

I'm in the final boss fight of the DLC and I'd like to do the fight without NPCs, but I'm not sure if that will affect their quests.

[McC1oud]

I think all the npc quest culminate in the previous fight. I'm not sure there is anything after.

I don't know this for certain.

[BKo]

Don't summon them they inflate the boss HP too much, and they drop their items whether or not you used them.

[Kefka]

nah, you have to summon npcs and they have to live in order to progress their quest-lines. yes you'll still get their equipment for most even if you dont complete the quests. this hasnt changed since demon souls

[Ronin Gamer]

I don't personally know myself. Some people comment that it inflates the bosses health and makes it more annoying and that you get their gear after. I don't know if anything else is achieved by having them in the fight with you or not. I'd have to look it up and currently since I'm trying to get through it I don't want that information right now.

[AcexXVII]

Yeah i couldn't complete the npc quests as they would always die and they inflate the boss hp so much

[Yes Man]

it required summon once i think

[Kefka]

there're ones like alexanders, i dont think you have to summon him at any point in time just talk at different points during the story.