[5] For his broadcast about Usain Bolt's triumph at the 2016 Summer Olympics, Costello won a Melbourne Press Club Quill Award in 2017 for Best Radio News.
[8] Costello was also nominated in the Best Radio Current Affairs category for his coverage of Muhammad Ali's memorial service but lost to Richard Baker and Michael Bachelard from www.theage.com.au for their podcast Phoebe's Fall.
But as the report was from the scene of a wall collapse in Carlton where two people had been killed, Costello felt it appropriate to apologise publicly and privately to the families of the victims.
[17] Concerns were raised in 2018 about Costello's unexplained absence from Nine News after reportedly missing calls and being absent for a number of scheduled live crosses.
[18] Costello later revealed he had been suffering from a period of burnout after working around the clock to cover a large number of international stories for the network.
[19][20] In 2019, Costello apologised for appearing to jostle with a Seven News reporter while the two journalists were working outside a Melbourne court, attempting to get a comment from a woman who had just been cleared of charges.