You're likely to find other trees that differ in structure (the relative order and grouping of branches) and specific names given to categories of fish.
Why would we post something that may prove to be incorrect? We may have made an error because we weren't careful enough. In that case, please let us know. But other uncertainties are at the forefront of science. The degree of uncertainty among the branches of the Tree-of-Life are variable. Some branches are well known and others, even for recent animals such as goldfish are remarkably uncertain. Another source of differences is in simplification that leaves out some things. Even so, we think that having some kind of tree is useful because it's a starting point to understanding, both for our audience of students and teachers, and us in moving towards building a resource that is useful and accurate at the same time. Let us know what you think!
If you need more detail, we refer you to: