Cracked foot on a good stick

[Garbandz]

58% is not terminal,in fact if your temp was in the 75-80 degree range it should be ok.
Sticks cracking is more likely from too much moisture or a sudden increase,or poor handling,of course.
Add moisture slowly, 1 % increase in 3 days is plenty,and let the cigars catch up gently.

63 to 65 % is a good average rate and will help protect against mold..........