What I found by searching Google is that mountain laurel is susceptible to a number of pests. Among them are borers, lacebug and whitefly. Also almost all of them will have something called cercospora leaf spot. I would suggest getting a good multi-pest spray for your shrub and it should help.

Could be shot hole fungus. If that's the case, you would need a fungicide. Take a leaf to a good nursery and see what they say.

multi-pest spray

Don't forget there are beneficial insects around too ....

Are the holes really so bad? Perhaps a good blast with the hose now and then will discourage whatever you have.