If a chicken has released a lot of moisture due to freezing, will these cause soup water to flow back in due to pore enlargement?
That release of moisture is due to breakage of chicken's cell structure, and further moisturing will not repair it - so it's not about the pores, and there's no "going back" from that state.
Still, if You cook Your chicken in a liquid with agents that affect osmotic pressure (salt, for example), it will lead to release of liquid through membranes, and further cooling will cause the reverse effect (chcken absurbing released liquid). 
That's why stew/soup-like dishes often taste better after cooling/reheating.

Hope I got the point)