My first career was in social work. We assessed transportation needs immediately with our clients at all 3 agencies I worked for over the years. Bus passes were the easiest, quickest service I could provide to my clients. It took far less time than helping with housing or food stamps. In fact I almost always had extra passes in my office or referrals to local churches that would provide passes or ride services. And yes some clients did sell or trade bus passes for drugs. Transportion is a big obstacle when it comes to employment and following up on appointments. I would check further with the social worker.
I agree with the suggestion to not give cash.
Good luck. This sounds like a very tough situation.