Country churches were never locked. You could wander in at any time. Perhaps Cromwell when he passed also found the door of Coldingham Priory locked and decided that he would get in anyway even if it meant removing a whole wall in order to do so.

Can we draw the following conclusion (choose your answer)?
Cromwell would get in anyway

(i). Yes; (ii). No; (iii). It's impossible to say;
(i).