Have been thinking about Des's loyalties too.
He worked for Dharma who's funded by Widmore, the financial backing is a question. But now that we "know" Dharma and the others are not one in the same, it is reasonable to assume that Desmond was backed by the others opposition during "the purge." He wouldn't be an other, he would be their enemy.
Des's loyalties lie to Pen and his honor.
agreed - and can you imagine what Charles Widmore is thinking now? If theories are to be believed about him being another one who 'nudges' people's lives into the employ of the Others/DI, just like MS Hawking/Brother Campbell/Libby(maybe - surely her boat donation was linked to all this?).
After he has gone to all the effort of 'bannishing' Des to the back of beyond to a life of button pushing and solitude, poor Dessie.