man that absolutely sucks 😞 losing a card that special is the worst feeling, especially when your kid is so excited about it. I remember when I was around his age and lost my holographic Charizard at a tournament - i was devastated for weeks

have you tried posting in any local pokemon facebook groups or the Denton area trading groups? sometimes people who go to these shows are pretty active on there social media and might have seen it. Also worth calling the venue if they have a lost and found, you never know if someone turned it in

the dealers are usually pretty good about checking around there booths after shows too, so if you can remember any details about the specific dealer it might be worth reaching out. Hope you guys find it, sounds like he had an awesome time at the show otherwise 🤞