Dear George,
Interesting! You have 'Natural Referrer' in Last Touch but unable to see the same in 'First Touch' which means your Marketing Channel 'Natural Referrer' is overriding every other channel.
Can you share the Marketing Channel rule for Natural Referrer? Guess some problem with the referrer i.e. Your internal domains were bucketing under your channel by mistake. Once we see the rule, we can help you.
Strong intuition is that your internal filters are not defined properly along with the Marketing Channel set-up.
Thank You, Arun.