Perhaps the possibility of losing Ladapo was a factor in the signing of Kelly from Bohemians but when the window closed, Rotherham had both - plus top-scorer Michael Smith, Will Grigg and Josh Kayode - after to Warne's surprise, no bids were forthcoming.
Kelly therefore faces stiff competition to play but he has already made a good impression, finding the net in a practice game between those players short of minutes recently and a mixture of reserve and youth team players.
Asked about he had settled in, Warne said: "Normally I would give you a real beige answer but the truth is he's just played in a game there and been really excellent, scored a goal, his first goal for the club a header from just outside the six-yard box from a cross from my son (Mack), so I'll just give my son a mention because as a dad I probably don't give him enough love.
"Georgie was excellent, ran around, was a real threat in the box and I was really pleased with him. Straight away the lads have taken to him.
"He's going to be a bit out of the first team but if something happens to one of my strikers I'll have no probem him putting in the squad, then it's about getting on the pitch.
"He knows he's got the painful road to get to the physical stature of the players here but he's got a real determination, he's a real clever lad, he understands.
"He's already started his programmes and he's progressing nicely so we're really pleased with him.
"He's and an amazing guy. You'll sit there and chat to him, you want him to do well and his team-mates want him to do well. He's a big part of our success here."
Warne says he has "no dramas" as he assesses the fitness of his squad after Tuesday's 5-0 win at Doncaster Rovers. The League One leaders host Accrington Stanley on Saturday.