Actually they are not. Even they claim to be separated from the RCC.
You and others appear to be unable to handle this religious fact of life, but I'll say it one more time for you.
Churches are classified as either Catholic or Protestant (plus some that are neither because their theology is so different from traditional Christianity, such as the Mormons), according to some basics of their beliefs.
In the Catholic category are the usual churches with Apostolic Succession, seven sacraments, salvation by Faith and Works, etc. -- the RCC, EO, OO, OC, Independent Catholic churches and so on. In the Protestant category are those that descend from the Reformation -- the Lutherans, Baptists, Methodists, Presbyterians, and so on. Some of them use as their standard name a general one like the Catholic Church or The Episcopal Church or The Methodist Church (now the UMC). But they're all in one category or the other.
When you try to make out that your own denomination is special because it is "united" while all those in the other group are divided, you're simply taking one denomination out of that category and claiming that it is one and united, whatever, while "they" are "divided." Of course "they" are.
One is always going to look more "united" than a bunch. But it's an illusion since the Roman Catholic Church has had the largest and most longstanding schisms in all church history and you're not comparing its category with the other category.
This argument could just as well be used with a comparison between, say, the 'Churches of Christ' and all the Catholic churches (RC, EO, etc), with the resulting claim, "Look, we of the CsOfC are one and united, but all you Catholics of different sorts are in disagreement and divided, so obviously you can't be teaching the truth. The truth is one, etc." In fact, that claim IS made, and it's no different than the one made by Roman Catholics in reverse.