The Londoners travelled to Cumbria at the weeked, where they lost 18-16, after trailing 18-4.
While Henderson was pleased with the character his men showed to fight back, he wants to see more quality in posession from them, especially as their next game is against Leigh on the Challenge Cup, on Friday.
“At 18-4 down we showed a lot of character to get ourselves back into a position to win the game so I can credit the players a little bit for that,” the former Scotland international told his club’s official website.
“We were under the pump and we’d done so much defensive work in the first half so to put ourselves in a position to win it was a great effort but again effort isn’t always enough.
“We’ve got to be better with the ball, more clinical with our decision making and our execution and hopefully we’re not in that position again.
“It’s very disappointing for the team and the club and I’m hoping the players will respond in a more positive manner this week in the Challenge Cup on Friday.”