I don't think it's the same. Kaido's horns have a curve then point up. The Silhouettes "horns" point straight up and look longer then Kaido's. And the silhouette shape looks nothing like the picture of Kaido.
It's not Kaido since we now know that Kaido is on the cloud island during that same time. I believe it's one of his subordinates possibly one of the same species as oars and oz