Where I work my manager was looking to fill an open position quickly. He is in a different state so there is a high degree of independence. He asked if I knew anyone for the job and I looked around. I ended up recommending someone that I met a couple of times, but is more of a friend of a friend.
He got hired. It seems that he has drug related problems. At work he asked if he could borrow cash from me so he could get his dealer to deliver some so he would have more energy. I said no. Another example is he was trying to pressure me into letting him use the company credit card to buy a coffee with because he didn't have his own money. He didn't want to ask for the managers permission, but I did (the circumstances made it somewhat reasonable, we were ahead of schedule to meet with a client so we were waiting in a coffee shop) and the manager said OK. The guy then orders 3x fudge brownies and eats them all at once. I found this very bizarre as he's not big. Also he is very incapable at times. For example he very frequently asks me what time it is. Last time I replied, what's wrong with your phone? He said "my hands are full" because he had his water bottle in one and cigarette in the other. He also takes very long breaks. He seems to try to avoid communicating directly with the manager and asks me to relay messages instead. Also he told me he offered someone else at the workplace his prescription drugs (presumably for cash). These are just a few examples, though I agree they are very circumstantial and hard to quantify.
I asked our mutual friend if he knew about these issues. He said he had been working in the restaurant industry where use of drugs is more acceptable in the workplace. This may be so, but in this work environment it's not.
Should I bring any of this to the managers attention, and if so how? Since I recommended him, I work closest with him, and the manager is in another city, the manager often asks for updates and asks how he is doing. Some workplaces, such as this one, actually give bonuses when you refer someone and they get hired. Why is this? At another job the person training us strongly recommended never to recommend someone. He said he did this with a friend, but when he was offered a job he ghosted the company. (Aside: Why would someone ghost instead of decline the offer or negotiate?) Is it bad to recommend someone for a job because if it doesn't work out it looks bad on you? This seems to be putting to much of the responsibility on one person, especially if you're not the one doing the interviews.
I never had a coworker ask me for money to buy drugs with so I'm unsure how to bring this up when a manager asks me how he's doing. How would you phrase that? Also considering he's a friend of a friend and I did refer him. Should I phrase it like "he asked me for money for drugs and acts low on energy and takes a long time to do simple tasks".