Oh definitely, but still, they will find out very quickly if that submission was worked on by several people day one when you ask them to do x task and they can't do it. It's a silly suggestion and borderline conspiracy theory for something that is not that important.
it is not a suspicion of false entrants. generally wonder how some of these small competitions are run (tho "Young Animator of the Year UK" would suggest it is reasonable size by now).
how would you avoid an entrant submitting pre-created or even some (obscure) work by someone else?
what are good prizes that incentivizes good submissions? how would you run such small competitions?
Because I think these small competitions could be super interesting for fostering skills among younger folks.
on the other side, what is in it for the organizers? is it best run as a charity?
Also, it's not a cash prize. The prize is a tour of an animation studio. Tell me what incentive would there be to falsify this kind of submission?