I think the skills of the programmer might make or break the project if you wanna go the procedural way.
I'm also not aware how you're going to proceduarally make a level in UDK... (It's built and baked, can't move BSP around can you? Unless you export them as a mesh?)
So then you might as well go with static meshes made in an external 3D package and at this point it doesn't matter what engine you use. Personally I'd advise using Unity... And perhaps use some tools for BSP like features like probuilder if you really need it.
UDK seems user friendly at first but it's immensively more complex under the hood for a project like this (students?) Unity would likely create less headaches if you have decent coder support, you can just focus on building what you want.
So I'll repeat, go with what the programmer wants. As a LD you'll just have to work around it but knowing that the coder can support the tools to make things work from a technical standpoint should make you go a long way.