Will using an NPC co-op sign allow other players to invade me?

[irl]

Elden Ring appears to use a fairly distinct formula for when you can be invaded by other players. If I understand https://eldenring.wiki.fextralife.com/PvP correctly, you can only be invaded by a player if:

• You're currently in a co-op session, and not already invaded (because the invader cap is normally 1).
• You're already being invaded, and you used https://eldenring.wiki.fextralife.com/Taunter%27s+Tongue to raise the invader cap to 2.
• You used a taunter's tongue to invite invaders even without co-op.

Naturally engaging in a duel also involves other players, but I'm less concerned about that scenario since I have to manually engage in it.

It's pretty clear to me that inviting another human player for co-op via a summon sign will open me up to invasion, but what's not clear for me is this: does summoning an NPC for co-op open me up to invaders? For example, if I summon Nepheli Loux for assistance, am I liable to be invaded by a player?

I ask this mainly prompted by https://www.reddit.com/r/Eldenring/comments/tf5rmp/infinite_falling_death_loop_hacked/ . I'd like to stay in online mode, but I want to know when I'm opening myself up to an exploit so that I can ensure my saves are backed up before someone messes with them.

[emran]

As far as I know no.
But I've got no sources to prove it's true (though I've tested it if the invaders can join my world with the kind help of Nepheli at the Godrick's area, after 10 mins no invader invaded me - not sure if it's luck or connectivity issues). So, take my answer with grain of a salt.

Luckily, almost all of NPC signs are at right before the boss area, or even inside of the boss area, so quickly enter the boss area, so that the invaders can't invade you.