I don't see how the search warrant and any evidence gathered could be thrown out. On 4/3, the original warrant was granted for CPS and DPS to go in and search for Sarah, and any documents pertaining to her, the "purported" husband, and any children from the "purported" marriage between the 2.
While conducting that search and interviews, CPS noticed other girls of teenage years that were pregnant and obtained information leading them to believe there were other cases of abuse going on. Based on that information, they briefed DPS, and DPS went back to the judge, who granted ANOTHER, BROADER search warrant for the entire compound and all documents, on 4/6. Based on the fact that CPS workers saw with their own eyes, and heard from other children that abuse was taking place, the judge granted the 2nd warrant. That is when the large-scale warrant was executed and the temple was entered.
I think TX authorities did this in a way that ensured nothing would be thrown out.