I also struggle with the dilemma of my biological offspring being homeless. But a few situation with a various friends of difficult child 1 recently opened my eyes to confirm that "we" as parents probably should not get involved.
Situations like the DEA popping in and destroying an apartment and the landlord deaming the leaseholder financially obligated to restore the property, sexual assault and battery charges sometimes incurs charges upon the property owner or any parent acting in "supervision" wherever the crime occurs, and civil liabilities and damages occurring to neighbors due to any crimes made me rethink ever possibly finding myself "assisting" with housing related issues.
It hurts, I know it does. But I think its very important that these difficult child's do not destroy any one else but themselves while they are on their destructive path through life. And somehow, someway, difficult child's usually find someway to continue their downward spiral after we as their parents struggle with the guilt, grief, and despair of their actions and of what they are doing unto themselves.
I try to picture it this way. difficult child 1 will either continue to "harm" and I will appreciate later that I did not get involved, or they will loose all control of their possible destruction and maybe the possibility of help will arise.
Best of luck to you, I feel your pain.