I think he did? The sigil is the gateway to the antiverse - as mentioned in the post that gives the sigil.
Are you experienced in soul travel at all? If not, I would recommend learning that first. Otherwise it’s a bit like… wanting to drive to California but not having a car. 
I have met something in my own travels that parallel’s Connor’s description, but it’s unclear if they are the same thing as the exiled beasts. I did not use the seal. I used a qigong meditation technique where you make yourself grow and grown until you are so large the universe is tiny and invisible, somewhere where your navel is. And then you cam move far from that. The universe does not end.
I called them “Leviathans”, because they seemed like whale-like creatures, so vast they make the physical universe look like a far away spec by the time you find them, out at the edge of the universe, as far as you can imagine.
They are of course manifest, as anything with a name must be, so they are not “outside of existence” and are not “exiled” - I don’t really understand why that word is used, there’s no spirit I can sense able to pass such a judgement on these things. But in my world, “god” or “source” is not a spirit, it is not manifest at all. It is the Tao.
The closest other parallel to these are the Lovecraftian entities sometimes called the Outer Gods, particularly Azathoth, imo.
They did not talk to me, they did not acknowledge my presence though I sensed there was an awareness that I was there, my telepathy skills were not refined enough to communicate. They just exist, floating and dreaming.