Drag and Drop with variable question

The reason it gets convoluted is that what you are attempting is very complex, whether you use variables or not.

Here's essentially the same thing, but it may be a little simpler with states. Look at the Incorrect layer. I've set up the Orange Bin, and one object in the Yellow Bin. (At least I hope the Sharps Bin is the Yellow Bin; I hope your learners have a better means of identifying them than I do.)

I set up the triggers and states to allow you to place the newspaper in the Orange Bin, and the needle into either the Yellow or Orange bin. I put a Test button to check my work as I went along.

This will give you an idea of one way it can be done, if you want to invest this many resources to it.

An option might be to make the drop zones large enough to accommodate all eight objects if they are tiled, and allow the interaction to change states when they are submitted.