There was the 9 oclock (aprox) that said there were sightings to the left front. Then a message was sent after Gardiner arrived, Gardner added to that message. Thats all from isandlwana itself, there were many sent of from Brown though. 3 possibly 4 I think.
Ive heard it mentioned that Durnford sent of a message while on the retreat, but thats all it has been just a mention.