The 33-year-old star recently claimed entertainment executives took advantage of the girl band's members, alleging they were ''all abused'' and had pressure put on them to ''sleep with whoever they say'' - but the Nicole Scherzinger-fronted group have denied such claims, saying they ''did not take place''.
In a statement to The Sun newspaper, they said: ''The Pussycat Dolls has always and will always stand for female empowerment and sisterhood.
''We stand in solidarity with all women who have bravely spoken publicly of their horrific experiences of abuse, harassment and exploitation.
''However, we cannot stand behind false allegations towards other group members partaking in activities that simply did not take place.''
Kaya - who joined the group in 2003 - also alleged executives tried to ''drug'' band members, and claimed she was warned she would be killed if she reported anything.
In a series of tweets, she wrote: ''Tried to silence us,made us stronger.Tried to drug us,but we were wide awake.Tried to blacklist us,but fans followed.We arent kids anymore
''The children you messed with that survived the abuse, we are adults now.Are you ready old ones to fight?Cause you all are looking mighty old
''My truth.I wasn't in a girl group. I was in a prostitution ring.Oh & we happened to sing & be famous. While everyone who owned us made the $
''How bad was it?people ask-bad enough that I walked away from my dreams,bandmates&a 13 million dollar record deal.We knew we were going to#1
''Robin & the record label made all the money. We as Pussycat Dolls were paid $500 a week. While we were being abused & used. Fact!
''Why don't we report it? Because we are all abused! I personally have been warned if I tell I will ... you know end up dead or no more career (sic)''
However, The Pussycat Dolls founder Robin Antin hit back at Kaya's allegations, claiming they are nothing more than ''disgusting, ridiculous lies'', and said the singer was ''clearly looking for her 15 minutes''.
Robin also insisted Kaya was only ever on trial and wasn't actually an official member of the group, which Nicole and Melody Thornton joined in 2003 alongside Carmit Bachar, Ashley Roberts, Jessica Sutta and Kimberly Wyatt.
American Thighs was released on this day in 1994.