my phone vanished at a repair shop

I honestly don't know what to do at this point and I'm looking for some advice. On Tuesday I took my iPhone 14 Pro to a local phone repair shop for what was supposed to be a simple repair. The owner told me it would take 1–2 days, so I agreed. After 2 days I went back to collect it and he handed it over, but it started overheating almost immediately after being turned on. He then told me he needed another day to sort it out, so I left it with him again. Today I went back expecting to finally get my phone, but instead he told me he couldn't find it. First he said he'd lost it somewhere inside his own shop and asked for another day to look for it. Then his story changed and he claimed that he had left it on the counter that morning and that some kids had come in and taken it. What makes this even stranger is that his CCTV setup is terrible, with basically one camera pointing into a corner and not covering much of the shop.

After that conversation I told my mum everything and she thought the whole situation sounded really suspicious. She told me to go back in and demand a proper explanation and mentioned that I should tell him I'd contact the police. When I went back inside, he laughed and said it was a civil matter and that the police couldn't do anything. I told him I'd let them decide that, and that's when things got even weirder. He said that if I called the police, he'd just lie and say he'd never met me and that I'd never brought a phone into his shop because there was no receipt and no evidence. The thing is, I actually have a voice recording from an earlier conversation where he's clearly talking about my phone and telling me to give him another day while he tries to find it, so that completely contradicts what he was saying. After talking about it for a few hours with friends and family, one thing that kept coming into my mind was how confident he seemed when talking about it being a civil matter and how nothing would happen if I called the police. It genuinely made me wonder whether he's dealt with situations like this before, because he immediately knew what to say and didn't seem worried at all.

At this point I'm struggling to believe his story. My biggest concern is that the phone has either been sold for parts or is otherwise gone. What annoyed me most was that his solution was to offer me £80 in store credit for an iPhone 14 Pro, not cash, meaning I'd have to spend even more money in the same shop after losing my phone. I'm only 16 and this whole thing has been incredibly frustrating. I also did some research and found that one of his previous businesses was liquidated, and his current repair shop appears to be owned or managed by his wife. I've already contacted the police, but I'm interested in hearing what other people think. Does this sound as suspicious as I think it does, and what would you do next?