Found my fiance on a dating app, he claims it’s an old profile

So recently I was trying to find a YouTube video in his watch history he wanted me to see, but I got curious and kept on scrolling (seriously I scrolled A LOT).. I noticed one video was a 30 second ad for a dating app. Not sure when exactly it was watched. I thought no big deal, it’s just a regular YouTube ad.. but then I had this nagging thought in my head that I should download the app and check it.

Not even 20 swipes through and I found my partners profile. My heart dropped when I saw his picture. I was going to try and catfish him to see if he’d respond. But I couldn’t hold in my anger so I asked him straight up about it. He said it was old, he hadn’t used it in ‘years’ (we’ve been together for 3 years) and he deleted it straight away. Now, honestly, he is TERRIBLE at texting/talking online (he’s the one word answer type). Even in person he’s not a big talker, especially with new people, but he is comfortable with me. I just can’t imagine him talking to other women. He’s never out or home late to make me suspicious of anything. We live in a small town so there also isn’t many people on the app in our area. And it’s a lesser-known app.

I just don’t know what to believe. He gave me his phone and I looked through his messages, messenger, call log, photos.. nothing out of the ordinary. But there’s no way of checking the app. What do you ladies think?