Trackables taken at my geocaching event and never logged — what should I do?

Hi all, I hosted a general geocaching event about a month ago. Several newly bought trackables went missing from the event. Multiple attendees independently told me the same kid took them.

The kid’s account has around 550–600 finds, so this isn’t a brand-new cacher. I messaged the kid and their mum with polite reminders and a warning, but they never logged the trackables or responded (left on read). This led to a lot of complaints from other attendees and trackable owners.

To prevent further issues, I later banned them from having a stall at a future event, but I’m unsure if I should take this any further.

My questions:

Is this something I should report to Geocaching HQ, or just advise owners to mark the trackables missing?

Is removing event privileges (like a stall) an appropriate response as a host?

How do other hosts prevent trackable losses at general events?

I’m not trying to start drama or punish a kid — just want to handle this correctly and fairly.

TL;DR: Hosted a general event, several new trackables disappeared, everyone says the same kid (with ~550–600 finds) took them. Reminders sent, no response. I removed stall privileges. Unsure whether to escalate to HQ or just move on — looking for advice.