I really like this one!!! I've got an idea now <3
Imma try to read more comment though haha and thanks for your time sharing ya idea
Edit: I have added the caretaker in my story so I really can't change it now.
Though I'm making him the reason why the boy and the man met... But it's still too unnecessary... Hhmmm...maybe I can use him as a character development for the mc like... Being more cautious
Hmmm. If he's already a part of it, and writing him out is too troublesome, then it might still be enough to just minimize his role and mentions (I recommend this method if you plan to get the backstory over and done with in one to two chapters).
Alternatively, you could also enhance his role and make him the true fourth node of the mcs backstory, along with the mother, the person behind the accident, and the old man. With rape plots one of the best ways to enhance their weight, bear with me here as I know it's unpleasant, is to let it happen. While almost being raped is a traumatic experience that can f up anyones life, in terms of fiction it's a little weak for mc motivation. Mc backstories are often straight misery porn and comparison is inevitable. That said, I don't actually recommend this method unless you really want to explore the long term ramifications of rape on someone's psyche as one of the themes of the story, otherwise the use of it could potentially piss off a lot of people instead.
What I'd actually recommend, if you want to enhance his weight, is to have him appear good at first. Have him comfort the mc when he gets to the orphanage, even make the mc think maybe the place won't be so bad after all, that way the betrayal really hits when his true colors are revealed. This way, the caretaker isn't just a way for the mc and the man to meet, the mcs interactions with the caretaker will subtly color his interactions with the old man, make him wonder his goals and motives, have the mc always watching him for a double cross, earn that caution you want the mc to learn(I highly recommend this if you're planning to spend three or more chapters on the backstory.) If you're interesting in this method but don't want to spend that long on the backstory, a shortcut is to have the caretaker and mc already know each other. Maybe have him be a friend of the family, or maybe say mc and his mom used to do volunteer work at the orphanage(makes her more sympathetic too). to name a few examples. It'll cheapen the betrayal for the audience but not the mc, so his character actions will still make total sense and the caretaker would've become integral to his story.
These are just suggestions of course, you should write the story the way you feel resonates with your vision best, my only hope with these is that they may give you some ideas on the potential of the characters. I hope your story goes well and I get to see it some time man.