Most likely. But the author of the article on atheism is talking about pantheism's resemblence to atheism, and the author of the article on pantheism is approaching it from another stance.
This is why looking at the labels people use and going no further is an exercise in futility and obfuscation. It makes no difference what word is used if there's no examination of what it represents to the people using it. "Pantheism" means a lot of different things to a lot of different people, with some of those differences being subtle differences in the way they experience their relationship to the universe and some more profound. There is no one "Pantheism" or one "atheism" and there never has been since more than one person started using those terms.
The OP question has a very simple answer: "Can you be both a [arbitrary classifier #1] and an [arbitrary classifier #2]? The answer to these questions is always a resounding and definitive "YES" because the content of the experience associated with a classifier is subject to change. And because it is subject to change, and does change, and means different things to different people at different times, one can quite easily be both at once.
Having read his responses, I gather now that the author of the OP
meant to ask something like the following: "Can you be both a [classifier #1, in the exclusive sense by which I intend it] and a [classifier #2, in the exclusive sense by which I intend it, which happens to be mutually exclusive of the sense I intend by classifier #1]?"
The answer to
that question is "NO." Though that question would not likely facilitate any communication or productive dialog.