There is no One True Visible Church.
Actually, there are Many Visible Churches, of which some portion of which are Truer Visible Churches, each of which is the assembly of immersion-baptized believer-disciples in a particular locale, subscribing to a Scriptural statement of faith, keeping all the commands of Christ watchfully secure without change, and maintaining its purity through strong preaching and church discipline.
Today, many of these will have created websites, enough to get an electronic cross-section of their doctrinal emphases. If you can't find them, it's because you didn't look. Don't bring any excuses here that you can't find the secondary differences that separate Presbyterians, Episcopals, Lutherans, Congregationalists, Baptists, and other common like-minded congregations. Do your own work.
Don't try to build a case that they are so divergent that nobody in them are unsaved. That won't wash, and it will just take up time, or be ignored.