I don't understand. There isn't a song in her discography where her voice sounds remotely like it. The singer's voice is a lot deeper than Bonnie's casual register. It's probably just some random backing singer. Bonnie's confirmed it's not her though.
Found a few things on the HFA Songfile which I thought were interesting.
Victimless Crime, the song with Max Martin and Klas Ahlund, won't show up when searching for Kesha. I've never really known why.
Bonnie McKee also has a song called Hush Hush, which may be where the rumours of her being on Kesha's song of the same name stemmed from, but it has completely different writers.
There are two versions of Supernatural registered, interestingly enough one without Bonnie McKee as a cowriter. I think the non-Bonnie McKee version is actually some Piano Tribute to Star Trek. What's even more interesting is that in the Artist/Album column for Supernatural, it has the following:
I'm really not sure what "Compilation" album Supernatural was on... any ideas?
Finally, Meet Me In Space, Young And Reckless and Not Obsessed are all registered, and all have the same writers. However, Meet Me In Space is the only one with "Kesha" in the artist column, and it's the only one we have a recording of. So I think it only lists Kesha's name in the artist section if she's recorded the song... which would suggest that MMIS and YAR are two different songs, not just a different title for the same song. Also Victimless Crime was most likely never recorded for this same reason.
A compilation release would be so cute. Just so it doesn't feel like nothing is happening. Even if it's all old songs.
Hush Hush is Kesha. There's a demo (no Bonnie McKee wannabe) with even shittier production (if you can imagine that) and it's clearly Kesha. Her vocals are a lot more processed on the "final" version with the dancefloor chorus, but it's still clearly her (if you're not listening to a pitched version). But it's not Bonnie and it doesn't sound like Bonnie.
It's probably one of the other girls from the I Kissed A Girl video lbr.
...
Also yes a compilation would be cute. Maybe Luke/Kesha are considering putting something out so her albums contract is up sooner, idk. Most likely not though.