Plasmid, that’s an impressively simple solution to all the n=3 mazes! Of course, the 5x5 solution is impressive, too!
Harey, this is a very interesting puzzle.
(a) and (b), haven't done (c) yet:
I assume a trial consists of all ants moving from one vertex to one other vertex. (In other words, we aren't asked about the probability of them never colliding, no matter how far they wander)).
icosagon
tetrahedron