It's great you wanting to help and you have contacted the relevant people to go out and try to help him. It is really difficult to know what each individual needs and whether they are genuinely homeless or if it's an easy way to get a lot of money from begging and then go home to houses better than ours, or if they have had help in the past and rejected it for whatever reason. The people who will come out to him are better trained to work out his situation than most of the rest of us.
Mind you, last winter on one of the coldest, snowiest days we went to Asda in a nearby town. Outside was a homeless young lady I'd seen before in the town centre itself (there are regular places the homeless tend to frequent, outside McD's, KFC etc with sleeping bags at night) She was freezing and looked unwell so I asked her if she wanted a sandwich and a drink. She wasn't begging, just huddled up in her coat trying to keep warm, not even making eye contact with shoppers and everyone was just walking past, not offering money, she was under the canopy trying to stay out of the snow. She seemed extremely grateful for the offer (or could be a good actor) so I went to get her something. I went back to check if she was vegetarian, had allergies, didn't like particular things etc and her responses indicated she would have eaten anything, as long as it was food.
Anyway, ds4 (7) and I went and got her a few things while dh and others boys started shopping. Sandwich, cans of pop, juice, crisps, chocolate bars, apples, bananas etc so she had something for later, some treats and some healthier food. (Also used it to explain stuff to ds about homelessness too as we have been classed as homeless ourselves and had to overstay at a house until we got our council house, and encourage him to be generous etc) She couldn't believe her eyes when I gave her the bag of food (she thought the sandwich was for her and the bag was our shopping) and was extremely grateful for the food, I will never forget the look on her face.
I hope we brightened her day and made it a little more bearable, I can't imagine she was out in minus temperatures trying to con people out of money in such misery, and I don't think that selling somewhere between £10 and £15 worth of groceries for pennies each would have produced enough money to buy a joints worth of drugs, so hopefully she had a couple of meals out of it. I haven't seen her since and sometimes wonder how she is and if she got any help she needs, but it is also in the back of my mind I could have been conned out of our hard earned money. There are plenty of people out there who are begging on the streets who make it harder for those in genuine need to get help.