In case that it is about the 8 pictures I can find in the link of sebcrea's signature, I can't find any similarities which are stronger than similarities of pics which are spread all over the net and even classical artists. The pics which are so close of sebcrea and Aaron Sims are not the most creative of Aaron Sims. He has more original creatures which differ stronger from the main stream of the general fantasy pool. And, sebcrea definitely didn't copy that ones.
To say it generally, there's no copying that goes beyond anything that was practise of the old masters of art.
