Very interesting, I think it's more than 1 witness. The Orlando Police report states two witnesses called the police about the scream.
Florence Harbor is also where JB had PI Lyon canvass the neighborhood for info, invoice below:
http://www.wftv.com/pdf/24312415/detail.html
Lt. Driscoll & Officer O'Day were just listed as defense witness, my guess is the defense will not make the scream the issue, but the fact that several OPD and OCSO officers with a K-9 unit, an aerial helicopter search did not notice or find anything, therefore Caylee could not have been there on 10/09/08. Also note the map, it appears that the officers parked on Suburban Dr. as with X's.
IMO, they can't make this work because of Mr. Kronk calling in August. This will benefit the State because once again, the area was reported to be under water.