I don't see how prayer can cause anything to happen, god's plan was perfect from the moment he conceived of it and implemented it, he's not going to change anything about that because it would be an admission of error, that the plan was less than perfect, and god doesn't make mistakes.

At best you might argue that god planned for one thing to happen if you prayed, and something else to happen if you didn't, so your prayer triggers some kind of action and perhaps there are two perfect outcomes, but... god knows which you will choose (he's always known) because he's all-knowing, and he allowed that to be the thing that happens, it's not possible that he didn't know what you were going to choose, so that's what's going to happen because he coudn't have made that mistake either.

So, prayer can't change a damn thing.