the original gospel had been lost but then re-emerged in the Philippines in its purity again. Their task was to be part of the reintroduction of the gospel, specifically to the people in the USA and America. I think this theory does a good job of explaining why there are divisions among Christians. Obviously until the gospel is reintroduced Christians will have to put up with their various divisions.
I think this church could be creating a new division.

If they believe they are
completely right and that the rest of us are
completely wrong then they are simply adding to the problem. It is one thing to say that you've got
something right, but quite another to say you've got
everything right and likewise to criticise another group for getting
something wrong and getting
everything wrong.
I disagree with and oppose fundamentalism but that doesn't mean I think it's completely wrong. I disagree with Catholicism but that doesn't mean I think it's completely wrong. I would rather that a religious community that exists for many good reasons and with few faults and flaws continue to exist as a religious community than to support a deeply flawed and malfunctioning community with few merits. There are many good reasons for keeping and maintaining the former, but not many for the latter.
I believe we all uphold parts of the gospel, but due to some ideological, philosophical and theological misunderstandings, prevent ourselves from pursuing the whole gospel.
I am frequently and consistently annoyed by the idea that just because there is one little thing wrong with a church it means you have to throw the
whole church into the rubbish bin.

It is natural and inevitable that factions exist. It is a political and ideological reality. Look at the secular world. It is inevitable that there will be differing views on what "policy" is right for us. Different people believe in different things being important. To deny the policy of another, you are denying that person's experience when it may be very valid.
As for me, I'm a pragmatist and I judge an idea on its value not on its "correctness." I evaluate ideas based on their social, political, emotional, communal and practical value. A religious community must decide for itself what is important and very often it will have to ignore the judgments of outsiders. I think it's inevitable that there are going to be "many fellowships." Paul chose not to argue with certain "troublesome individuals" not because he probably saw them as heretics, but I believe because he accepted that people were going to have a different "policy" when dealing with matters affecting their respective local communities. Dissidents simply belonged to another fellowship.
I make a distinction between factions and divisions. Factions are just groups with different policies and merely believe that other factions have inferior policies. Divisions are groups that truly believe everyone else is a heretic. I'm talking about separatists here.
I think Christianity will grow and mature if only we come to accept that "many fellowships" is a reasonable thing to have. I believe it is right for churches to "mind their own business" not in the sense of denouncing and vilifying other churches that can't conform to their ideology, but in the sense of deciding what is right for themselves. Different fellowships are not to interfere with each other's internal affairs unless someone has been hurt and there is seriously something wrong with that fellowship.
I think I should say the same macroscopically of dealing with Judaism and Islam. We are not to interfere with other groups, whether that is within, or without the tradition of Christianity -- nor to allow outsiders to meddle with Christianity internally (usually it's the other way round, however).
That isn't to say there shouldn't be co-operation between various groups . . . that is external. Joint ventures will be taken when people are ready to share. Once they have taken care of their internal needs they might start looking outward.