Correct, and also must have purchased a B-flex fare on SN (which is their LCC equivalent of J -- so even buying J doesn't get lounge access ... an interesting extrapolation of the LCC model). More to the point, an AA J codeshare US-BRU-Europe would not have lounge access without paying the EUR 15 fee. Note a departing BP at BRU is required to get to any of the lounges, so it isn't usable for any arriving pax.