First, his citation of Riefer is nothing more than a general opening statement that the court could use his declaration as his testimony. It is a common case used in a lot of opening statements.
Concerning cases that discuss changes in custody and visitation. There are too many to count.
The basic premise is that there has to be a change of circumstance in the children’s lives to modify custody. It is possible to modify visitation with a lesser standard.
As far as child support goes it is also a change of circumstance test since the last time support was modified.
Custody, visitation, and support are some of the most highly contested areas of family law and you need to discuss your case with an experienced family law attorney. Sorry I could not be of any more help.