He used a pen name (or pen initials) at Sick, which had came to Charlton to end its run. This article, "Who's Watching What" from 119 (Feb/78) is signed D.E.K. in the final panel; as it happens, its script (credited on the splash page) is by Popeye writer Bill Pearson.
The best place to look for any artist's style would be secondary figures, but here I chose a panel of Sappo from a Wotasnozzle backup to Popeye, because his straight-to-the-side pose, with a head almost perfectly round, is typical of Wildman, like the character George in the Felix tier below. In the Felix stories there are backgrounds of massed clouds with a few distant birds by their edges; the same can be found in Wildman's Popeye stories.
So George Wildman would be my guess on those two Felix stories.