Watson-Siriboe played the entire 90 minutes as RSL (13-7-3) kept the pressure on Western Conference leader San Jose.
And while Olave didn't play, continuing to nurse a minor knock, Wingert and Grabavoy did eventually make their way into the match in the second half.
"It's been good," said Watson-Siriboe about playing his fifth game for RSL. "The coaching staff had a lot of confidence in me coming in and it's given me the ability to continue to push forward even when I make mistakes. Every week you make mistakes, but it's something where you have to learn from your own mistakes because you have to press forward. The coaching staff has continued to give me confidence and Nat, too, that if I make a mistake they won't take me out; it is something that will continue to help me progress and advance my talent."
Alvaro Saborio scored a goal in each half for Real, which had to withstand a powerful Vancouver assault in the second 45 minutes. The Whitecaps scored midway through the second half and began peppering goalkeeper Nick Rimando with shots.
Even down to 10 men Vancouver keeper Joe Cannon was sent off with a red card for handling the ball outside the 18-yard box the Whitecaps continued to attack and eventually sent 12 shots at goal in the second half.
Rimando praised the play of his newest teammates.
"They were good, really good," he said. "Kenny is a young player and is very great in the air, and Kwame is as well. He's very fast, has good positioning, and talks a lot so I feel comfortable with them in front of me, especially when I have Nat [Borchers] back there. It makes it all easier because he has good positioning and he communicates very well with those two, so it makes their job easy."
Real Salt Lake makes a quick turnaround, leaving Sunday on a chartered flight for its CONCACAF Champions League game at Costa Rican champion C.S. Herediano on Tuesday.
"We all know it's tough though," Borchers said. "It's not going to be an easy place to play. The atmosphere is going to be very negative toward us. But it's going to be fun, a great challenge. We're ready to get back into CONCACAF."