Well there is TWO issues here
1- Big hide means, no security so that could be a huge issue look for these and buy the appropriate size one.. http://www.reptilebasics.com/hide-boxes
2. If meal is TOO small they may refuse to eat it. a pinky is tiny unless live it is not very "enticing" Look at the girth of your snakes mid section (widest part) and find something similar to little bigger for his next meal.