Whitecloud made it 2-0 at 5:56 after receiving a cross-ice pass from Mark Stone and scoring five-hole, but Givani Smith cut it to 2-1 at 10:19 with his first goal since Feb. 7.
"Confidence goes both ways, offensively and defensively," Red Wings forward Sam Gagner said. "The only way to get it back is through work and making sure we're detailed. We're making errors as a team that's trying to grow and forge an identity. We have to be better in those areas."
Whitecloud scored his second of the period at 12:32 with a shot from the point to give Vegas a 3-1 lead. Forward Nicolas Roy had an assist in his 100th NHL game.
Cotter made it 4-1 at 19:06 with a wrist shot from the slot.
Reilly Smith increased the lead to 5-1 at 5:19 of the third by going forehand to backhand glove side before Veleno made it 5-2 at 18:34.
"We have one more game here on the homestand and we've got to take care of business, but so far it's a testament to our group, system, coaches, everyone," Lehner said. "We're fighting through a lot of adversity. Really proud of the guys and the young guys that have jumped in."
NOTES: This was the Golden Knights' first win against the Red Wings at T-Mobile Arena. … Whitecloud became the fifth Golden Knights defenseman to have a multigoal game (Dylan Coghlan, March 10, 2021; Alec Martinez, April 5, 2021; Shea Theodore, Nov. 27, 2018, Feb. 1, 2019, Jan. 20, 2021; and Nate Schmidt, Dec. 4, 2018, Dec. 27, 2019). … Red Wings rookie Moritz Seider left in the third period after blocking a shot with his right knee. There was no update. … Detroit forward Dylan Larkin had an assist in 15:58 after being pulled after the second period Tuesday against the Dallas Stars due to COVID-19 protocol. … Theodore did not play after hitting his head on the boards on Tuesday against the Carolina Hurricanes. He skated Thursday and is expected to skate again Friday, but there is no timetable for his return. … Forward Sven Baertschi had one shot in 13:54 in his Vegas debut.