Any Text Claiming to be from God is Very Likely Not

[CHOOCHOO!]

Then I'm afraid I don't see the point of your post. Who cares how unlikely something is to happen. You can't use this argument against a religious person because it doesn't say anything other than it is unlikely for something to happen, which doesn't mean it can never happen therefore you don't have a point at all.

Who cares? Clearly not theists I guess. Isn't it pretty illogical to believe something is true when there's no reasoning or evidence to suggest it as such, AND there is also reason to believe it is actually false?

Nobody will probably ever find an argument that states "X religion is false" and "X religion is very likely to be false" is as close as anyone will get. A lot of theists cling onto the misguided belief that their god and holy text are likely to be true, so proving the opposite is at least worth something imo.