Guest posts on a blog during a week-long coding conference for an open-source encrypted communications project aren't different enough for you? Hard to imagine any one of these posts as something other than hacker news.
If it is indeed true that you are in fact multiple people and have independently submitted articles relating to your (actually pretty cool sounding) event, may I suggest that you coordinate in the future to keep the articles submitted to just a few at a time, and make your comments more substantial.
This would probably stop the accusations of you running an Astroturf campaign.