The Tigers were in control at that stage but it did not take long for Wakefield to claw their way back into the game; James Evans and Jason Demetriou touching down to ensure that they went in at the break holding a 14-11 lead.
Captains Danny Nutley and Monty Betham exchanged tries in the opening eleven minutes of the half leaving the game poised at 20-17, before the tries from Henderson and Evans to secure survival for the Wildcats.
Wakefield coach John Kear – who has guided his side to four wins from six to keep them up – was jubilant after achieving his objective.
"We have worked really hard for two months and the players responded absolutely sensationally. We have done it! We are in Super League, and that is what we wanted” said Kear.
"We expected Castleford to come out and put their foot on the throttle but we just said if we play through it we would come through in the end, and so it proved."
Captain Monty Betham was just as happy to stay in the top flight – but admitted that he felt for Castleford.
"I thought I was playing in a Test match” he said. “There was a lot riding on it but I don't like relegation at all and we really feel for everyone at Tigers."
Castleford boss Terry Matterson commented that silly mistakes had cost his side, yet there was no lack of effort; adding that he was preparing to find another job.
Matterson said: "There was no lack of effort but our execution was poor. We prepared well and got ourselves in a great position but there were some uncharacteristic mistakes and decisions.
"I am out of a job now and have got to look for another one. But I am confident in my ability as a coach, and that I will still be coaching at the top level, wherever that is."
Tigers captain Danny Nutley will now have to return to Australia on a sour note and admitted that the shock had not yet hit home.
"In a high-intensity game like that you have got to hold the ball and they did a better job. It hasn't hit home yet but it is so disappointing."
Castleford will retain a full-time squad in National League One next season and will be one of the favourites to win promotion to the Super League.