Why not connect the video output of the device in question
to one of the video inputs “composit or S-video” of the Canon XL1.
Then turn the XL1’s operation dial to VCR, then roll to record.
IMHO, you don’t have enough lights to get great results
lighting three people and a backdrop properly.
But that doesn’t mean that it can’t be done.
Get your lights out and practice lighting this scene before the shoot
with stand-ins, so you will have a better idea of your final setup.
If they have the budget and are looking for original sounds,
Then hire a good sound designer to create original sounds for your animations.
If the budget is minimal and they don’t care if the sounds are used in other animated shows,
then just do a google search and pick from one of the many libraries out there that the other guys are using.