Good questions.
I am not convinced J&L even knew what they meant,they’d have been going off tales told by others, I personally doubt either had actually summoned an unbound 4 before.
However, there are plenty of legends about what the high powered demons can do in those circumstances out there on the Astral plane.
For example: prying into the minds of the recipients via empathy/telepathy (not clear what) and extracting the conjuror’s deepest fears and then creating illusions, or realities that attack the conjuror with their deepest feats.
Mind games, illusions, all sorts of trickeries and deceptions, Perhaps turning to mist and seeping through the holes in the magic net
When there is a group, do fear attacks on the weakest link, try to break the circle of power. If it knows spells it could cast counter or neutralized spells.
Now as to the whip..
First demons and other exptraplanars (in their true form) can only be hurt by magic items or iron based items (and in some cases silver or other metals)
The whip was leather, dead flesh and Tom didn’t even notice it, if he’d noticed it, it would have hit him but not hurt…think of it being similar to his flame form which is insubstantial.
Live flesh with animus in, would have touched him whether he knew it or not.
The sword was iron, or perhaps steel, which contains iron. So therefore he felt it, but it wasn’t sharp enough to hurt him.
Talarius, later on, had a sword with iron in it and it was super blessed/magical.