What do you intuit is happening in this introductory romantic scenario?

I met a middle aged woman through a friend. I didn't think to ask her out because she was in mutual flirtation with him. After talking to him thinking it was just a matter of time before they were an item, he revealed his reasons for not being interested in her at all.

1) She's older than him (40 something) although she looks younger.

     1a. No one he knows dates older women, only younger. He's only into 20 somethings.

2) She has a 16 year old son that she dotes on.

Days later, I thought about my conversation with her and realised I was very interested in her. I mentioned it to my friend and he reiterated his thoughts while transferring them to me. He strongly stressed the fact she had a son and I didn't want to be with someone who had a child.

He added that she had a good job and is self sufficient so she wouldn't be interested in a guy who made significantly less money. This was finished off with a classic "I'm not gonna tell you what to do..."

His reasoning is illegitimate and he's being a terrible wingman. I never asked him to be one, but he's been completely negative. I asked him to keep it to himself and found out the next day that he didn't keep his mouth shut. 

I don't know if he likes the woman, or what. If he does, I would step aside as he knew her first and has formed a bond. If not, I'm not sure why he isn't encouraging me, or getting out of my way, or giving me valid reasons to not date her.

If you have thoughts on this, please share them.