The BATF had enough information to warrant legitimate concern about illegal activities at Mt. Carmel. The most serious allegations were about sexual abuse of 11 and 12 year old girls. The BATF was still wrong in conducting a military attack of the Davidians' residence. Sexual abuse is not in the realm of the BATF, rather it is the realm of state law. The information should have been passed to the proper authorities for further investigation.
Allegations are just that.
In the U.S., people accused of a crime are considered innocent until proven guilty. Investigating allegations does not justify a military assault. The affidavit used by the BATF to gain a search warrant made note of the fact that David Koresh opposed gun control, believed U.S. gun control laws were wrong, and possessed a Gun Owners' Association video portraying the BATF as violating gun owners' rights by threats and lies.