This isn't just limited to "No One Left Behind" since there's multiple IPs I can't seem to get anymore, including the one where you save Arabella for Wyll. Patch 6 just did something to IPs and it's annoying it isn't working. Hell, I can barely find any information about the problem, so it's unlikely to get fixed anytime soon, or at all as Ecc2ca said. It isn't a widespread problem, hence less attention on it.