I fail to comprehend why this guy I like and had a brief fling with want to, suddenly, hook me up with another guy he knows. He told me that he won't tell him anything about what happened between us because he respects me and cares for me. I mean I didn't ask for his help to find a guy. Why is he trying to be a good Samaritan.

Plus, he gave me mixed signals regarding his interest towards me. He goes full force into contacting me talking to me, finding me on social media adding me back as a friend. Liking my profile picture where there is just me in them. He also knows that I like him

Anyhow, I told him indirectly that I wasn't interested.
Because I'm not attracted to that guy. Despite him telling me he is soft spoken and good character. I can't put my heart in it. To that he added well if you change your mind let me know. ''I'll put you in contact with him and you guys can take it from there.''

Side note: I lot of guys do ask me why I'm not married because I'm good looking and attractive. That I'm getting old (31). Won't be able to have kids after a certain time etc. (This guy is slightly of that opinion too)

Maybe he is gaging your interest in him by mentioning the other guy? Maybe he thinks you are not into him? Maybe he's just odd? Could be many different reasons.

Do you think I should tell him that I like him at the risk of looking like a complete loser?

His motives don't matter! Only how YOU feel, so you tell him no thanks, and stay out of your business. Under no circumstances do you tell him you like him, because it's rather obvious he doesn't feel the same, or his way of showing it is insulting, and dishonest, so like him or not, UNFRIEND him.

I don't mean to be so harsh or blunt, but that fling didn't lead to anything more, and you don't need his sympathy, nor pity and it's none of his business what you do with your life. Who ended the fling and why? Do you know anything about this guy he wants you to meet? It's just too weird a situation for you to be involved with, so remove yourself, and get fling dude out of your life. I find it insulting a fling would think it's okay to pass you to a buddy.