Rovers' first-half performance was dreadful and they rarely managed to string a series of passes together before County midfielder Joss Labadie rocked them with a spectacular 25-yard shot which flew into the back of the net following a 14th-minute free-kick.
Doncaster managed to raise their game slightly after the interval, but were unable to pinch an equalizer with Billy Paynter and Iain Hume having shots cleared off the goalline.
"We've got some young lads in the side and it was tough for them to come here against the leaders in front of a big home crowd," Kiwomya said.
"But I told them to go out and show what they could do - and they did that.
"Doncaster put us under a lot of pressure at the finish, but we battled our way through it and a bit of magic has won us the game.
"There was no fluke about Joss Labadie's goal. He strikes the ball really well and is always capable of doing that.
"Unfortunately for Doncaster we had a bit of luck as well as a bit of quality. We came here and showed our pride and it's laid the foundation for next season."