The referral program definitely works and isn't a scam. It's entirely possible your coworkers didn't use your link properly. 

That said, if you think they used a device that's never played Raid before and used your link, you can open a support ticket. 

It works for me so I suspect they didn't click the "Trust" button in there? Or maybe they opened the link and then proceeded from different direction. 

Both coworkers stood next to me, had them download, texted my link. nothing worked, watched both hit the trust button and let the data be collected. So let me know how its not a scam if its suppose to work

the only time it has worked for me, was when i downloaded the game from my brother in laws link

If they hit the trust button, it means it's registered. If it's an issue of not being able to collect rewards when they hit the required levels then you should open a support ticket.

Not working properly =/ scam, there is a distinction there.