Nolf competed with the Nittany Lions from 2014-19.
American will travel to Penn State on Friday, February 21, just before Penn State heads to Big Ten Championships.
Retherford will compete in his first Olympics in the 65-kilogram freestyle category.
Barraclough held a 15-13 record as a Nittany Lion.
Lee will take over for Jimmy Kennedy, who left Penn State to work for David Taylor at Oklahoma State.
Kerkvliet is set to return for his sixth and final year of NCAA eligibility.