A foreign resident helping a Japanese friend

This is a sensitive topic. It concerns what is culturally appropriate and acceptable, in terms of helping a Japanese friend in a desperate situation. it involved people 50 years old and above.
This Japanese man's health is so bad they have been in hospital recovering, after first being dismissed but subsequently collapsing again.
He is a man living alone with a very low income and in poor living conditions. A friend who is a foreign man visited their home and was horrified to find the friend living and tolerating a tiny home totally cluttered with filth and trash. No condition anyone should be living in. Clearly, the man is not able to take care of himself for health and financial reasons. Clearly he needs help.
It needs an intervention from the friends who care about him, but the foreign friends also don't want to humiliate him by crossing the cultural boundaries. It seems absurd that culture and shame would trump the act of care and help that friends could give to improve his life, but sadly it seems like there are very strong cultural boundaries that make this true.
What do Japanese people think? Should his friends just turn a blind eye and continue letting him live helplessly? Will it really be worse if the friends intervened and offered help with an"oo-soji"? And some financial support?

Would really appreciate your thoughts and opinions from Japanese people, thank you so much.

I believe you can get in contact with the city office. They will contact the person on your part and assist the person in need, if there is any.

My wife mentioned this about a homeless man that we've been seeing around recently. I suppose the city office would send someone out and see where they could help him and how.

I believe if the person you say is truly unable to take care of himself and is humble about it, the government would step in and find home care for him.

In the meantime, I've found people to be truly respectful if approached in this manner. They likely will refuse it, but if you persist, they will eventually take the help and there will be no hard feelings. As mentioned about the homeless man, we have given him dinner countless times. The first time was the most difficult, but now that he knows who we are, he'll take it and thank us, which is obviously enough for us. Unsure if we're going to pursue going to the city office to see if he's been reported yet, etc.

I mentioned the city office part because this seems like an ongoing situation. If your friend is going to care for him, he should continually do it without break... that would be a drain on them pretty quickly when we're talking cooking, cleaning, etc. versus reporting him so that care can continue and your friend can merely drop stuff by every once in a while.

Thank you so much for your considerate and empathic reply, and for shedding light on these possible ways to act.
It's good to know that that city office can be contacted. And i do trust that Japanese people are full of kindness.
Your story about helping the homeless person is moving and very hopeful. I think extending these gestures of kindness and generosity in daily life are beautiful and important for the fabric of a humane society. You never know how much of a difference you could be making for a person.

I'm sure your friend will take kindly to whatever you choose to do, be it food to money to whatever. However, in this particular situation, I would try to get him permanent help. Helping him will become a task after a while, and that is not a path that you might want to particularly take--at least, I would sleep on that decision.