From top to bottom, Engelhart is attacked by two rats, and keeps out one of those that tries to sneak past him. A 15 misses, and a natural 20, doubled, causes 6 damage. Engelhart had 30 hp, now 24, and is not stunned. Hurt, though.
Valda is attacked by one rat, which she stops from getting past her. The rat misses with a 4.
Lotharis attacked by two rats, which he keeps from breaking through. A 14 hits, as Lothar is AC 8 according to my notes, causing 1 damage. Lothar has 28 hit points and is not stunned. The other rat rolls a 10 and misses.
Embla lets a rat get past her; it attacks from her flank, while another attacks from the front. The one on her flank manages a modified 9, missing. The one in front rolls a 12, also missing.
Rob is attacked from the front; the rat does not try to get past. It rolls a 14, which hits AC 7. I am not certain of Rob's armor class, as I haven't had time to look at any character pages. Please let me know whether or not that hits.
MEANWHILE ...
A large, grey, jelly-like creature,
definitely not an ooze, emerges from 0612 and flows into 0711. It has a large membrane at its center.
The players are free to take an action.
Following the players' move, here is the layout.
And the experience thus far: