I think you misunderstood. We aren't saying that the series could theoretically end in +1, we're saying it doesn't end. so it would be 2z=2-2+2-2... If you place a 1 at the end it would mean 1 of 2 things. The series would end with +1, which it can't, or after the infinite series, you get a +1, which would not make sense, but even if it did it would never get to it. (Since the series is infinite) So im not completely sure what you meant, but the math doesn't work out for a series. Also, the article got that point wrong, as already mentioned. Therefor, I am not inclined to agree with this article. That is like saying there is evidence of teleportation but you messed up 2+2 in there.
Thanks