Welshman Cornell moved to Saints on a one-year loan but lost his place in goal for last week's Scottish Premiership trip to Hibernian.
He was dropped by boss Danny Lennon after conceding 10 goals in Saints' first five games but former Blackburn trainee Dilo could not prevent the Buddies from going down to their latest defeat.
However, Dilo did make a number of decent stops and is favourite to hang on to the number one jersey for Monday night's visit of Aberdeen to Paisley.
But the 19-year-old Frenchman insists the two keepers will work together to help St Mirren register their first win of the campaign, no matter who is starting between the sticks.
He told Press Association Sport: "David and I are still friends. He lives in the same building as I do and we talk all the time.
"We don't see each other as competitors or rivals. We are friends really.
"It's different for goalkeepers than outfielders as there is only one position and for me to play, David cannot. But it's not a rivalry. It's just down to whoever works the hardest and whoever is in the best form.
"The keeper who is playing the best will play. If David plays instead of me, or if I play instead of David, there must be a reason. But we are still team-mates and we support each other."
Aberdeen travel to Paisley in contrasting form to their opponents, who have lost seven of their eight games this season, drawing the other.
The Dons have won three matches in a row and kept five successive clean sheets.
Pittodrie defender Mark Reynolds said: "We will now start to get more media attention because of the run we are on but we just have to deal with that. We want to keep the run going as long as we can.
"It's nice people are taking about how well the young boys have done since coming into the team and are not talking about which players are out injured."
Aberdeen could have Niall McGinn and Barry Robson back but Willo Flood, Russell Anderson and Chris Clark remain out while Andrew Considine is a doubt.