Yes, the ball was placed in the wrong spot (intentional or not, probably not). Yes, the penalty is valid since penalties have nothing to do with "intent". Yes, since she wrote the wrong score she should technically get a penalty for that as well.
So on paper, there's nothing wrong with what they did. But it's the how & why that's B.S. If the USGA wants to use video replay as a part of the game just like most other major sports these days, fine. But they need to do it THEMSELVES just like every other damn sport on earth. They need to have a team of people that sits and monitors the video feeds, and if they see something then they can call a rules official and have them go take care of it ASAP. A reported penalty shouldn't be able to come from any other source, except obviously from another player or caddie who witnesses something in person the course. And there should also be a time limit, like you can't assess a penalty once the next hole has started - or at the very least once a round is completed. In sports like football, baseball, basketball - once the next play has started, the previous play is over, no going back and changing anything. And those are all fairly fast moving sports and they're still able to have enough time to review anything that needs to be reviewed without interrupting the pace of play too much. So with golf - which moves at a snails pace - they shouldn't have any trouble monitoring each hole as it is played and report any penalties before the hole is finished. And if you do allow penalties to applied later in the round, then at the very least make it so once a round is completed and a score card is turned in then it's written in stone and can't be changed. Or if you do decide to allow penalties after the round is over, then don't also assess the scorecard penalty. Because what happened this weekend was horseshit. Allowing people to call/email/tweet about something they saw on TV is abso-f-ing-lutely ridiculous.