Find My Iphone

My son lost his iPhone 11 on Friday, October 22nd. He had it at school with him in the morning, and then couldn't find it afterwards. We have Life360, and I saw that the phone looked like it was at the front of the school when he was first dropped off, around 8:15 am, but didn't see any other information on it. He said he used his phone after arriving, so I'm thinking he might not have had proper network, so Life360 never updated.

Anyway, after school, I logged onto iCloud with his ID on my android phone, and his phone was showing Offline. No location data was available. His iPad was showing as in my apartment. I checked a few times Friday, and nothing. Friday night, my son checked Find My Iphone on his iPad, and it showed that the phone was last seen at 6:12 PM that day, near the gym. I contacted the Gym teachers, and they checked first thing this morning. The school is fenced in, and the gates are locked after school on Friday, so in theory, no one should have even been able to have access to where his phone was showing as last available. The teachers checked this morning, and couldn't find the phone. I set Lost Mode and notify me when available right after school, at around 3:30 PM. According to Find My Iphone, Lost Mode is still pending.

So, I have three questions...

First, why was his device not showing a last location when I logged in from my phone or from my

computer? Why would it only show on his iPad?

Second, if the phone showed a last location at 6:12 PM, it would seem as if the phone connected to the network somehow, so why wouldn't Lost Mode have been applied?

Third, as of about 15 minutes ago, the phone is still showing the same location at 6:12 PM on Friday. I thought the Last Location only showed for 24 hours. Is that not right?

Are there any other options here? Is there some type of weirdness going on, with the location tracking?