Not necessarily, only that he wasn't one of the planners.  According to The Squad he was arrested in Vaughans Hotel because he wasn't registered and he hadn't a toothbrush.  He had come with Peadar Clancy and then been "forgoten about".  The question is, if Clancy went to Vaughans just for an IRA meeting, why would he bring a civilian? Doesn't it seem more likely that he was in Dublin on IRA, but not Bloody Sunday, business?