I want to make some animations of sims leaving the Electrolux wormhole generator. Can it be done? I know you can substitute an existing animation, but there are no animations of a sim leaving the wormhole generator.

Yes, there are no real tutorials on the process though. Basically you need the animation itself imported into a clip file (same process as poses), an ASM (animation state machine) referencing your clip file, animation tuning, then you need to edit or create an interaction that references your animation tuning under the basic_content section of an interaction.

Tutorial on poses and then a tutorial about object animations but it explains the general process you'll need to know (just skip the object oriented stuff/look for the sims equivalent).