i was researching admin And i was wondering if he had ever attempted to work alongside the omega timeline so they could keep in touch with it's allies and free from interference, after I thought that, i remembered that admin is VERY NOSY, and would prob listen in on stuff he's not suppose to hear, so maybe made core has limits to what he can do? and ink helps him talk to creators as long as hes not nosy and wont take secret info and give it to the enemy (nightmare gang)
Admin is SUPER nosy! CORE!Frisk is aware of this, but they're also aware that he doesn't intend to do much with any information he learns (other than blurt out embarassing information about someone to their face). Admin is obsessed with knowledge, but he's not an information broker or anything of the sorts. He just likes to know stuff.
He has a door in the Omega Timeline which he's embedded his code into. But he finds it difficult to observe the OT unless he's physically close to his door, making it pointless to connect to the Undernet Protocol. CORE!Frisk knew this too, so they just left him alone for the most part.
(As there's no Undernet Protocol there, Undereats - which functions through it - will not work in the Omega Timeline either. But you could always ask someone to collect the food and bring it to you?)
As for Ink… I don't believe he's able to talk to the creators? He benefits from them, but as far as I know that's it. Either way, he wouldn't tell him - Admin has a habit of entering timelines and making them multiverse-aware, which can affect their intended story. So Ink doesn't like him very much. They've fought over it once or twice, but Admin keeps coming back and Ink keeps forgetting about him.
(Admin doesn't care about Nightmare and his group, so doesn't interact with them)
(CORE!Frisk belongs to dokudoki
Nightmare belongs to Jokublog
Sorry for the wait anon! Hope this answer is satisfactory :] thank you for the ask!