Anything Goes : A Question on Ethics by Colm Ó Searcóid

Hello People! I'm new here, so I'm still putting together my profile. Haven't introduced myself yet even! But this has been bugging me all day and I'd like some perspective on it. So this is going to be my first post here. I was recently approached by a potential client to create a series of acted testimonials for a product the client is selling. The product is those Binary Trading options. Now, the example testimonials I was shown were so fake I laughed - some woman does this and in a week made $600k and so on. So it's quite obviously a scam, so most people would probably just laugh at the videos if I make them. But what about those few people who might buy into it? Should I decline the job offer because ethically speaking, I'd consider myself complicit in duping gullible people? Any thoughts?