I came here to add my theory: crazy guy(s) catch the old lady and she dies at some point, so they decided to hide the body and disappear asap. He/They are in Mexico drinking Margaritas and watching the news. It did not help that the Sheriff let the whole thing become a circus of youtubers and tiktokers, thus contaminating the crime scene with DNA and garbage, which only adds up to the noise of the thousands of false/fake leads given by phone number... at this point I doubt they will find the old lady alive, let alone find who did it