If you didn’t catch (or want to see again) the 2018 Children in Need sequences with Jodie Whittaker and team, you can do so here: Children In Need 2018.
Not only is there a long clip from Kerblam!, but in the Children in Need sequence where the children visit the TARDIS, it looks to me like they might just be in Cardiff Castle and the new Doctor Who exhibit.
As to the clip of Kerblam!, it’s all very jolly, and a bit Time Heist. I just hope the fez isn’t a sign of too much channeling of the Eleventh Doctor. Not long before we find out!