Looked on foundation website also after the Q drop. The webpage with the pic was lined from the top banner item. Used inspect on the pic and the meta line for image indicated the George Floyd pic was uploaded from twitter on May 30.
Other Anons explained how the dynamic imaging stuff like when you change name or icon, so satisfied it was uploaded after the murder.
They followed their motto, never let a crisis go to waste. Think the used the pic to help fuel the racial injustices and knowing that riots and looting would accompany peaceful protests.