b) The entire leader's circle goes: You, Martel, Oisin, Sylpha and the Seeker. The silent show of solidarity will let the Tuatha know you stand by your word, and your friends. The presence of the demon and one of the banishes may be affronting, however.
c) You, Martel and Oisin will go. Sylpha and the Seeker might be offensive, and between the three of you, you make a fair representation. The exclusion of the Seeker and Sylpha may cause an internal rift, however.
There you have it. Vote! Share! Good luck!