Similar happened to me years ago. I hired a plasterer and on the second day he brought a teenager with him - a sickly looking lad, who just slumped in the van most of the day. By 3pm the plasterer had had enough and said he’d take the lad home, as he was neither use nor ornament.
A couple of weeks later, I noticed some jewellery missing and called the Police. It could only be the plasterer, so the Police went off to see him. I was surprised a few days later when the plasterer turned up with everything, except one ring, which he thought had already been sold. He said he was sorry and explained that the lad was on drugs, constantly in trouble with the police, and as a favour to the parents, he’d thought bringing him out on jobs would give them a break and keep the lad away from local bad influences. I believed him and was sorry that his good turn had backfired.
Like others, I’d mention it to the boss and query if any of the lads had simply moved it somewhere for safe-keeping. Hopefully you’ve already changed those passwords.