As noted, WWE NXT trainer Billy Gunn was fired from WWE last week after he tested positive for performance enhancing drugs back in July at a powerlifting competition.
WWE was not aware at the time that Gunn had failed a drug test, or was even competing in the powerlifting competitions, and just recently was made aware of his PED use.
According to F4WOnline.com, the reason why Billy Gunn had not previously failed a drug test in WWE is because according to the company Wellness Policy, WWE only drug tests talent, and not coaches or trainers at the Performance Center.
However, once it became known that Gunn had failed a drug test, the company decided it could not have one of its trainers failing a drug test and continuing to work at the PC as it makes the entire developmental system look bad.
WWE officials are reportedly considering two people to replace Gunn, but no official decision has been made as of this writing.