It's a solid game and it works well. I kind of like that you can focus on one, then do the other. The keys were a great idea forcing the characters to work together, as opposed to trapping one character then completing the other safely.
I do have a few suggestions on changes. The sound effects need to be turned down; they are way too loud. The fake spikes should have some indication on which ones are fake or not, unless I missed something.
Great job!