Other mistake: The security guard alerts Batman about Barry Allen's arrival pushing a button on his phone. The date on the phone says it's Friday 20th Jan, which is coherent with the year (2017) this version of the movie is set in, but too early for the K-pop "As if it's your last" music video playing in Flash's lair (it was a summer release). (00:16:50)
Other mistake: The janitor, Howard, stops Dr. Stone to talk to him about the loss of his son. Look at his badge; the person on it sports a beard and sideburns and a hat, and it's "Jensen" plus initial. Later on the same janitor hears a noise inside the lab and you can see the badge picture is different and it lists the full first and last name. The first scene was a Whedon reshoot, so probably after weeks they didn't have the original prop and made another one. (00:18:55 - 00:21:15)
Answer: "Surely they'd figure it out" is hardly a suitable solution. If they knew how to destroy them, they would have. They did the next best thing by hiding them in different places.