Cowan secured the services of 20-year-old Yates on a season-long youth loan from the Championship club at the start of this month.
And the youngster has helped Telford to a 1-1 draw with National League North leaders York City and a 4-1 win over Guiseley 4-1 since making his bow.
The Derby goalkeeper enjoyed loan spells at National League South side Gloucester and Telford’s divisional rivals Hereford last term.
And Cowan said Yates’s experience was why he was able to send 21-year-old Andy Wycherley to Hednesford until November 23.
The boss added: “Andy has gone out on-loan to Hednesford now.
“He is still in a very developmental period of a very young career.We plucked him from TNS where he had not really played a senior game, he was playing in the lower echelons of the Welsh league.
“He’s got a lot of developing to do, but a lot of attributes that I believe he could be a good goalkeeper.
“He’s not gone away to stay away.
“He’s gone away to learn his trade because we felt at the moment playing for Telford might be too much of an ask for him.
“So we brought in Matty, who is proven at the level and a very hot prospect for a club like Derby County.
“He has come in and performed brilliantly well.”
Meanwhile, Cowan says skipper Shane Sutton will be out for a few more weeks.
He said: “Shane Sutton has probably got a couple of weeks yet – there is a lot of soreness around the injury. The injury itself has healed, it is just about trying to eradicate that soreness now.”