Moneys shark does not spawn in Duck Tales

Playing Minecraft on Xbox, multiplayer, my two sons in Iceland on the same machine w split screen, and me in Norway, both machines running the latest update of Minecraft for Xbox, and the latest update of the Xbox OS. 

Bought Duck Tales on the marketplace. In one of the  earliest  missions, the Money Shark does not spawn, thus preventing further progress in the game.  

Having watched a walkthrough online, I switched over to creative mode and manually spawned the money shark, and subsequently also manually spawned the money shark w legs. 

This allowed some small progress, but as soon as Lena/ Magica de Spell should spawn, she didn't, halting further progress completely, even though one tried manually to spawn the right character. This was extra frustrating because one gets locked inside the McDuck manor. 

This caused some small sorrow with my 9 year old.