The teenager, who cannot be identified for legal reasons, had been invited to Jones's NSW Southern Highlands property after corresponding with the veteran broadcaster for years.
He had been 13 when he reached out to the older man about his family's difficulties.
The now-adult man's mother told a Sydney court on Tuesday their situation had been dire and she was incredibly grateful someone of Jones's stature was willing to help.
"I was desperate," she said.
The court was told the former Wallabies coach advocated on the family's behalf, liaised with political and financial contacts, and spent more than $100,000 supporting them.
The teen's mother said Jones predominantly discussed details of support with her son and told him not to disclose certain aspects to her so she wouldn't worry.
She said Jones told her he saw himself as a mentor for her son and someone who would always be in his life and care for him.
"I was so pleased to have an older mentor in (my son's) life ... someone who saw my son was as intelligent as he is," she said.
The mother was "really comfortable" with the 17-year-old visiting Jones for a weekend during the school holidays, telling the court she trusted the longtime shock jock.
She had not been invited to stay, nor to join them for previous meals.
But when the teenager returned, she said she knew straight away something had happened.
"He wasn't sleeping ... he was withdrawn," his mother said.
After consistent questioning, the teenager handed her a note ten days after the visit and said: "I don't want to talk about it".
The note recorded that someone had done something they shouldn't have.
She asked if the teenager wanted to go to the police.
"I wasn't raped and it probably isn't a big thing in the scheme of it," the mother says he replied.
"It will be my word against him and he's a powerful man."
Her son alleges Jones kissed him with tongue in a hallway and grabbed his bottom without consent, prompting him to recoil and step away.
"That's enough, Alan," the 17-year-old allegedly told the broadcaster.
After reading the note, the mother told her son to have no further contact with Jones.
But she continued communicating with the former ruler of Sydney's airwaves about her son and the family's difficulties.
"I was scared the assistance that had been given would be quickly removed," the mother told the court emotionally.
"It embarrasses me that I kept in touch with him but I did."
She broke down in tears several times while giving evidence.
Jones denies the one count of indecent assault against the then-teenager and 20 charges of indecent assault and sexual touching without consent against four other men.
The alleged incidents occurred between 2003 and 2020 - the latter half of his highly influential, three-decade broadcaster career.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
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