What should a person do if they find themselves in a place where halaal can only be attained by doing something مكروه (disliked), and they cannot live alone or do without this halaal?

If the question is about makruh tanzihi (disliked to the point of being reprehensible), for which one is rewarded for abstaining and not punished for committing, then this dislike is removed for the slightest need. There is no blame upon you if you need it and find nothing else.

However, if makruh means haram (forbidden), for which the perpetrator is punished, then it is not permissible to embark on it except in a dire necessity. It is not permissible to violate it without necessity.

When good and evil are indistinguishable, it is obligatory to consult trustworthy scholars. Wisdom dictates preferring the better of two good things by sacrificing the lesser, and repelling the worse of two evils by committing to the lesser. This is a deliberation exclusive to scholarly rabbis, and not for ordinary people. Every incident requires specific consideration.