Simmons tested positive for the deadly virus as his bandmate was recovering and the group was forced to scrap a series of shows as both stars completed necessary isolations.
The rockers were back onstage in Irvine, California on Thursday night (09Sep21) to pick up the band's rescheduled farewell tour, but the concert didn't go exactly as planned - Kiss had to cut their set short due to an approaching lightning storm.
Stanley tested positive for COVID on 26 August (21), forcing the band to immediately cancel that night's performance in Pennsylvania. Days later, bassist Simmons also tested positive.
Kiss will continue their End of the Road tour in Mountain View, California on Friday night.
Meanwhile, Coldplay will become the first act to play Seattle, Washington's new zero-carbon arena.
The eco-conscious musicians will open the Climate Pledge Arena - the world's only concert mecca powered exclusively by renewable energy - on 22 October (21), a week after the release of their latest album, "Music of the Spheres".
The concert will also be livestreamed on Prime Video.
All fans aged 12 and over will have to be vaccinated in order to attend the gig.