1.) Can an organism adapt to the exact same outside influence in different ways?

2.) Can free will be attributed to chaos and random occurences within the organism itself?

Saying yes in number two makes number one impossible to answer except on a theoretical level. If we accept chaos we can hardly accept that situations that are identitical on every physical level will ever happen.

What we know for a fact is that an organism can react to very similar outside influences in different ways.

Humans are even prone to take actions that would seem to contradict completely with the swarm intelligence of a random gathering of cells.

Not conclusive evidence for free will, but its better than nothing.