Bryan Danielson jumped from WWE to AEW, making his AEW debut at All Out just months after headlining WrestleMania.
Before leaving WWE, Danielson spoke highly of wanting to work wrestlers in different promotions and WWE was reportedly willing to make that happen.
According to Dave Meltzer of the Wrestling Observer, WWE promised Danielson the ability to work for New Japan Pro Wrestling and Vince McMahon gave him permission to wrestle in the G-1 Climax Tournament.
Meltzer goes on to report that AEW and WWE offered Danielson similar money and WWE would allow him to do limited dates as well.
In May it was reported by Meltzer that WWE and NJPW were "in talks" regarding a potential partnership and that Danielson was the "main crux" of the negotiations.
The relationship between AEW and NJPW ramped up during the pandemic with NJPW allowing KENTA to work on AEW Dynamite. Since then, Yuji Nagata, Satoshi Kojima, and Minoru Suzuki have appeared on AEW television. Prior to the pandemic, AEW talent would work NJPW shows in Japan, but didn't wrestle on American NJPW shows and NJPW talent were not featured on AEW TV.