The Washington Diplomats survived their first-ever guaranteed win situation last night, edging the Dallas Tornado, 5-4, in North American Soccer League indoor play before 2,429 at D.C. Armory.

The Tornado played without Kyle Rote Jr. who did not make the trip to Washington. He has still not signed a 1978 contract. The Dips announced prior to the contest that any fan who felt entitled to a refund because of Rote's absence would receive one by mailing his ticket stub to the Dips' ticket office.

The Diplomats, with a 4-2 record after stopping a two-game losing streak, will meet the Tornado again today at 3 p.m. It will be the Dips' final area appearance before they host the Chicago Sting in regular-season play April 9 at RFK Stadium.

Kenneth Mokoja, who arrived Friday from South Africa for a one-month trial, debuted successfully by putting Washington ahead, 4-3, with 7:02 left in the final period.

Art Welch, who has scored in every Diplomat game, tallied what proved to be the winning goal with 3:14 to play. Gene Mishalow provided the assist.

Steve Newman's unassisted goal narrowed Dallas' deficit to one, 5-4, with 23 seconds remaining, but the Dips held on to save management a few dollars. If the Dips had lost, last night's ticket-holders would have been given a general admission ticket to this afternoon's contest.

Both goalies played well. Washington's Eric Martin made 28 saves and counterpart Ken Cooper 21. It was Dallas' first indoor soccer game since 1976.