Stereochemistry of epoxide hydrolysis under acidic conditions
Standard epoxide opening in acidic conditions would happen at the more
  substituted end


This premise is false. Usually $\ce{S_{N}2}$ is faster than the cation-stabilized pathway (most textbooks don't even bother to explain the subtleties involved), yielding mainly the less substituted (less sterically hindered) product. It is not clear cut which of the two mechanisms will be predominant in an acid catalyzed epoxide cleavage given the reactants and reaction conditions.

See also Regioselectivity of acid-catalyzed ring-opening of epoxides (especially the second answer and then the excerpt from Clayden et al.).