The West Yorkshire club host Salford Red Devils in Super League at the weekend - just six days before playing St Helens in the showpiece next Saturday.
Given the scheduling, Powell has taken many of his frontline stars out of the firing line and teenagers Cain Robb, Caelum Jordan, Jack Sadler, Adam Rusling and Nathan Magee could all come in for their first appearances.
“It’s a Sunday into Saturday Challenge Cup final which says it all really,” said the coach, as he explained his decision-making.
“We wanted to play on Tuesday and that didn’t happen which then created a whole host of issues.
“Take head knocks, for example. If anyone gets a head knock (on Sunday), they can’t play (at Wembley due to protocols)....
“We wanted to move the game but couldn’t because of Covid.
“It's an impossible task really but what it does do is give us an exciting young squad.
“We had our licence taken away and then given back for the youth academy and this gives us a great opportunity to showcase these young fellas and I’m really excited to see them play.”
With Tuesday’s game at Huddersfield Giants called off because their opponents could not raise a squad due to injuries and Covid - Castleford being in the same position the previous week when they had to forfeit their game against Saints for similar reasons - some of his players will have not played for nearly a month when they step out at Wembley.
“There’s a risk both ways and it’s not ideal,” said Powell, as Castleford bid to win the Cup for the first time since 1986.
“But when you see a Tuesday, Sunday leading into a final, it is what it is.
“The risk of putting a team out on Sunday was - I felt - too much, to be honest.
“I made a decision there, that's what we’d do. There’s a couple of boys who wouldn’t have been fit anyway so we're making conscious decisions on players who aren’t fully fit, making sure they are right for next week.
“Some of those decisions have been taken out of our hands but clearly there are some decisions that I’m making to make sure that we have the best possible chance next week.
“We just got to do our best as these next 10 days are absolutely crucial for our season. We have to get it right.”
And, with Covid infection rates on the rise, that is where some players have been going the extra mile.
Powell explained: “For the last few weeks, we’ve been talking about not going anywhere that is going to open you up as an individual (to Covid) and us as a club.
“There’s not much you can do if wives are going to jobs and kids are at school; with infections it is so hard.
“But there have been some serious sacrifices made by some of our players, taking kids out of school ten days before the final and wives are working from home.
“The boys are doing everything they possibly can to get us to next week with no disruptions. Look around and it’s a tough ask; we’re all doing our best to make sure we get there with as little issues as we possibly can.”
Asked if that was something the squad had come up with, Powell replied: “It’s not everybody but certain individuals.
“Michael Shenton's taken his kids out of school. Paul McShane's wife is working from home, and they are two making those kinds of sacrifices.
“They see it as that important. There will be others but for these boys it's a huge part of their lives - playing in a Wembley final - and for the players who get there it is absolutely massive.”
Captain Shenton, 34, is one of those who is in the Castleford 21-man squad for Sunday along with Grant Millington, the Australian prop who missed the final in 2014 and is now looking to prove his fitness as he comes back from a knee injury.
Powell said there are still a “couple of places” still left up for grabs in his Wembley 17.
“Obviously, Grant Millington hasn’t performed for a while,” he said.
“Alex Foster will be out there, Jesse Sene-Lefao, Cheyse Blair, Danny Richardson, James Clare…
“There are some places available and players need to play well. They are aware of that.”
Castleford 21-man squad: Shenton, Richardson, Watts, Millington, Holmes, Blair, Foster, Hepi, Clare, Sene-Lefao, Eden, Bienek, Peachey, Martin, Hall, Robb, Qareqare, Jordan, Sadler, Rusling, Magee.