The truth is you will have got nowhere near establishing the existence of your God.
The situation is akin to claiming that because the police have shown that the murderer lives in this village, so they're close to showing that Bert, who lives in the village, is guilty. Actually, they're clearly nowhere near showing that.
And if there's good evidence Bert didn't do it (he's got a good alibi, let's suppose) - well then the police case against him is utterly demolished!
The theist's claim that they're at least near to showing God exists above is equally ludicrous, and only fails to seem so in their eyes because they mentally airbrush out all the other candidates (like a policeman mentally airbrushing out everyone else in the village but Bert in order to convince himself the case for/against Bert's guilt is balanced).