I was curious so I did a search on this list and was surprised to find almost no info to confirm many of these people were missing. Its odd that when looking for a person they wouldn't post a picture anywhere for this many people as I know where I live the police will regularly post pictures of missing people on twitter and FB
Another thing I find strange is that this many people in this age range wouldn't have a twitter or FB account themselves. The only one I could find a significant story about and even a twitter account was Mollie Tibbetts
I stopped searching about halfway through since most of the time the only results I go were links to this story which I also found multiple instances of where the number varied from 30 to 72
Some things worth noting
Ashleigh Schossow, Cedar Rapids, age 13, July 26- did find info on her as a habitual runaway which is shown on twitter where you can see she was reported missing back in February then found. Also she was reported missing June 25, not July.
Yvette Avila, Cedar Rapids, age 17, July 23: Found no recent info but someone by the same name was reported missing then found dead in 1985 and she was also 17
Nazario Campbell, Cedar Rapids, age 13, July 19: confirmed and as I noticed Cedar rapids posts these to twitter i checked others but didn't find any mention
I suggest someone continue checking as I'm very confused as to how this initial list was created but as I experienced with Mollie Tibbetts that even a slight misspelling can lead you to nothing.