A Met spokesperson said the woman who Mr Airlie is believed to have fallen into was of south Asian appearance. The force added she also fell on the escalator.
Mr Airlie is also understood to have spoken to a woman on a bus travelling from North Greenwich underground station, who gave him a tissue for a cut above his eye.
At the time, he was wearing a black t-shirt, light grey jogging bottoms and had a turquoise and grey Mountain Warehouse rucksack.
He was also carrying a medium-sized black suitcase.
Det Insp Chris Rogers said: “Mr Airlie’s death is tragic, and his family continue to mourn the loss of a loving son, partner, brother and uncle.
“We are determined to piece together the events, and give Mr Airlie’s family the answers they are searching for. You can assist us by coming forward with any information.”
He added: “However small it may seem to you, this could be the key we need to unlock the investigation.”
