That's quite a big sum they scammed. I think this is totally a scam trick and a phishing attack was there. It's been happening for a quite long time now these days.
what do you guys think about qualities needed for new projects to avoid scams like this? 
Quality? Have not heard this for the last few months or years? lol. Almost all the projects on yield farming are total scams. Some do it earlier, some on a later date. It's even quite easy to launch a project, make it tradeable on the market. So, it's easier to scam with yield farming.