The band's invitation to play the event was rescinded today after Jackson's estate complained about old comments Gene Simmons made about the late King of Pop.
So what did the sharp-tongued singer say that resulted in the uninvitation?
Following Jackson's 2009 death, Simmons proclaimed that there was "no question in my mind he molested those kids. Not a doubt," referring to the numerous allegations leveled at the pop star. Jackson was never convicted of any such crimes, however.
Howard Weitzman, a lawyer for Jackson's estate, sent a letter to the organizers of the Oct. 8 concert in Wales, complaining about the inclusion of KISS. That prompted today's surprise reversal.
"Global Live Events has pulled them from the lineup.We have listened to Michael's fans and are grateful to have been alerted to these unfortunate statements by Gene Simmons," said Global Events CEO Chris Hunt.
"Under the circumstances we fully agree that KISS is a band Michael admired we have no choice but to rescind our invitation to them to appear in our tribute concert. we offer our sincerest apologies to Mrs. [Katherine] Jackson and the family for this oversight. Our primary concern must be to do justice to Michael's memory, and to put on a tribute that the family and the fans will find suitable and fit for a King, our King of Pop."
In his direct response to Weitzman, Hunt also suggested that, the next time the estate wanted to discuss plans to honor Jackson's memory with Global Events, perhaps they wouldn't reach out "through an open letter."
There was no immediate comment from the usually outspoken Simmons.