The win lifted them off the bottom of the table to 19th, two points from safety.
"Before this game, I said that if you ask 100 persons of football, they will all say that we will be relegated", he explained.
Watford had taken the lead on 11 minutes, Andre Carrillo heading in after Richarlison's shot had been saved. We know we can do better things with confidence. Me, my players, my chairman, the fans, we are not part of this 100.
"Now we have a tough game on Tuesday, we need to rest and to learn from our mistakes", added Kabasele.
And then sub Luciano Narsingh netted the victor three minutes later after Watford keeper Heurelho Gomes had failed to hold Nathan Dyer's long-range shot.
The hosts appeared to be cruising to victory after Andre Carrillo's opening goal, but they failed to capitalise on their comfortable position and, after 86 minutes, allowed Jordan Ayew to equalise.
"We finished the game trying everything, two attackers, two wingers, (Renato) Sanches in the middle, (left-back Martin) Olsson playing like a winger".
Gray's failure to finish after being played through on Fabianski looked set to be a footnote in a relatively comfortable Watford victory, but Ayew and Narsingh punished that mistake in emphatic fashion. It was incredible that we got rewarded because we really worked hard.
- Swansea scored a 90-plus minute winning goal in a Premier League game for the fourth time and for the first time away from home since April 2014 at Newcastle, when Wilfried Bony scored their victor that day. "We are disappointed with all of us as I think we did enough to win this game; we controlled the match, we had more chances than our opponent and at this level we need to score to win".