Emails have been released in which the Russian singer - who recorded telephone conversations in which Mel makes threats to her and tells her she was a "****" - reveals their 11-month-old daughter Lucia was offered a "generous gift" but there was "nothing" in it for her.
In one email obtained by gossip website TMZ.com, Oksana wrote: "As far as the tapes go, I only played one to my lawyer, because on March 15 Michelle proposed on ur behalf not a very generous gift for our daughter and there was nothing for me.
"My lowers also told me that Tom Hansen [one of Mel's lawyers] said I wouldn get a penny. (sic)"
However, her lawyer Daniel Horowitz has revealed she was reluctant to play the tapes to him, because she didn't want to "hurt" the 'Edge of Darkness' star.
He said: "Oksana was legally entitled to play all of the tapes for her lawyers and most clients would have done so.
"She was being supremely careful of Mel's privacy because she knew that even lawyers in Hollywood might lose track of the tapes and she didn't want to hurt him."
Responding to suggestions she was "extorting" the 54-year-old star, Horowtiz added: "This is the opposite of extortion. It's someone in love who wants things to get better."
Earlier this week, text messages were revealed in which Oksana tells Mel he treats Lucia like an "illegitimate child".
She said: "U keep saying that ull take care of us in the most generous way. I wouldn't have played ur messages if u were keeping ur word. Even if u were just generous to Lucia, that would have been great. But u weren't. No where near the way u r generous with ur other children. U treated her as an illegitimate child. That's why I played the tapes. And my name wasn't mentioned at all. (sic)"