Travis was fine with her taking pics on his camera. He didn't know he was going to be brutally slaughtered by a psychopath and could have deleted them when he chose, had he remained alive. Why would he trust her to take pics of him naked on her camera?
My guess is that she showed up, apologised profusely for the blackmail attempt, convinced him that he could take pics of her as an 'insurance policy' should he doubt her promise not to reissue the blackmail threat. She may have given him the cheque (check in American language) to sweeten him. Her hair is dark in the pics, not blonde.
Arias wasn't bright enough to wipe the photos from the camera. Beyond grasping for excuses in the interview with Detective Flores, the 'memory card swap' seems utterly implausible. Juan Martinez gave no credit to this theory. Not impossible just improbable. Why would she premeditate covering her tracks in Arizona yet leave evidence on the camera?
The reason I find this theory strange as it's buying Arias' attempts to deflect and lie to Detective Flores with no good reason. Even Arias doesn't take it further. I don't get why this seems significant to some, genuinely.
TrialWatcher......
I've reconsidered. I think your theory about the pics as insurance policy is brilliant. It fits. Perfectly.
Why May 26, if she had already decided to kill him? To unveil, with maximum impact, the sex tape (hence need to run to bishop, stat) and to make him fear being exposed, as she had after he threatened on April 7, that he'd tell everyone who mattered to her about all the "psycho" stuff she'd done.
Making him feel that fear was only part one of her plan. I think the only reason he replied to her again after that was because he felt he had to.....that she'd act on her threat (directly or indirectly) if he didn't.
I really think she began planning in earnest by late April, and that included lining up Ryan Burns. Burns served two purposes.
He genuinely was to replace TA as husband candidate after she killed Travis, but she lined him up beforehand to lull Travis into not freaking when she surprised him in his own house on June 4.
The call to Travis on June 2 was to tell him she had come to her senses after the May 26 fight, realized how much she'd hurt him, and that she really now was able to move on. And that trip to Utah she'd mentioned? She hadn't wanted to tell him, but now that they had both really moved on, her trip to Utah was to see someone she thought might be the One. Wish her luck and all that.
So he didn't freak when she surprised him in his office on June 4 where he was taking a break from cleaning his tile floors. Earlier, she had watched him from outside, then after he'd gone to bed, entered the house, snooped a little bit, then took his journal to read as she hide in his car, maybe his phone too, waiting until she was sure all his roomies left for the day.
They talked in his office. Sex came up, she suggested it for just the reason you think...an insurance policy, so on his camera.
That scenario I can see. He didn't want to have sex with her that day. He didn't like her and didn't trust her, but she was offering him a way to guarantee she wouldn't expose him with the tape.
Now that she had found her One, she had as much at stake as he did that the tape was never handed over /a confession of transgressions made to a bishop. And if he didn't believe her, sure, sex photos on his camera.
She deleted them afterwards, not him, but didn't say so on the stand because it took her too close to the truth.
Travis thought she'd left before he shaved and took a shower, she surprised him again there, with a gun.
Theory of the day, anyway. The pics as insurance policy resolves for me why he would have had sex with her that day, because I'm convinced he had seen her for she was and was scared of her.
He fell for her scheme because he thought he was being released from the hell he'd been in, that it was going to be possible after all to marry and to have the life he thought he'd thrown away/had been taken away because of that .
ETA...JM saying the tape was "to make him do something." Right. Have sex with her that day, which would lower his guard and get him into the shower.