The news has been asked about the search warrants release & another document dump. I'm tired of proding them. FOIA request have been filed but if the LE aren't releasing them, must be a reason. My guess is they do have a suspect(s) but without Isa, her body, a confession or say someone telling the truth about anothers alibi, they might be stuck. Same as they were with Haleigh Cummings, Lisa Baldwin, Alya Reynolds and so on.
We can guess that TPD focused solely on the parents but actually they went to great lengths checking Mexico, California tips and other states back east. They questioned each family in a 3 mile radius 2 times at least & searched their homes, checked videos, searched the small lakes, washes, the dumps and have made other searches we don't know about. They have methodically approached many other scenarios. They have even stated they had several directions they were investigating, 4 was the last I remember. It has been a thorough investigation from when we were privy to updates. Getting search warrants when the family said they could search the house. It appeared to me they did everything by the book so that when there is an arrest & trial, some defense lawyer can't say they didn't do this or that. Having only 2 full time investigators was a shock to hear but if they just need that one piece of the puzzle obviously they haven't found it yet.
If a parent was the last to see Isabel, first to notice her missing, blood found in her room & there was evidence he shouldn't be around his boys, then it's a duck to watch. Notice the parents this week on the news still would'nt answer the question if the family was reunited. It appears that Sergio does have visitation privelages at least though.
Hopefully, someone will step forward with information of where Isa is but I won't hold my breath sadly. Seen it too many times. jmo