Collaborations are shared on a pack-by-pack basis. When you set up your collaboration, your collaboration will only be seen by packs you choose. These can be packs you own or are a member of. And within those packs, only people that meet the minimum qualifications you set for you collaboration will be able to apply.
If you only want to potentially collaborate with a few Perlu members, simply create a pack with just those influencers. Only they will see your collaboration, so you won’t be spammed with hundreds of potentially non-relevant responses.