My question involves a child custody case from the State of: AR

Minimizing clutter, in nutshell, divorce and joint custody was set in 2004. At the time of divorce the mother was working out of town. She was not sure as to what part of the state her job would take her. She spent the weeks in another city and spent the weekends in the home town of the ex. She agreed at the time that "joint custody" would allow the lions share of the kids time with dad and she would get weekends. She spent many of the weekends in the home town using he parents home as a temp residence. Approximately 2-3 months later she landed a permanent position with her company about 2.5 hours away. She and Dad agreed upon a meeting place and she then started exercising her visitation time in her new home town. 3 weekends a month and split holidays and summer.
2 years ago Dad remarries and as is sometimes the case, new challenges arise with time and flexibility with the children. During this time, mom travels to dads town for kids activities. She spends weekends there when they have things going on. She travels the 2.5 hours each way on week nights for band concerts, parent teacher conferences, school plays, etc. Dad carried many of the day to day expenses but mom buys clothes, medicines, and part of their insurance, etc. As well as provides the children each with their own rooms, fully decorated and loaded with books, toys, stuffed animals, etc.
A year after dad's remarriage, dad files for full custody, child support, etc. Based on the Material change that the kids are older and so the old arrangement does not work any longer. Also that mom has scheduled a couple of doctors appointments with the children during her time with the children.
At time of court, the shift of material change moved to "mom relocated" after the original decree 9 years earlier. While that is true and is technically a material change, it was a change that was in place and worked for 9 years.
In testimony, the children testify (which the agreement was the children would NOT be called in and yet they were "surprise" witnesses with the only notification being Mom seeing one of the children in the hallway of the courtroom 5 minutes before court began). The children definitely followed the "talking points" of dad and step mom in stating that they miss out on birthday parties and sleep overs because of having to see mom. Also they testified that mom never comes to their town nor any of their events. They state clearly that spending an extra weekend with Dad per month will make all better. Dad claims in his own testimony that two specific events the children missed were 2 and 4 years ago respectively. However, even though he states they communicate by email or text, he had no record of ever having asked Mom about the two events but he knows that he did.
Mom provided email and text communication directly regarding her traveling to the kids town for ballgames, PT conf as well as many other events. The emails were coincidental communication with Dad that just happen to also include dialogue of her active involvement with the children.

I know this is brief, however, my ultimate question is: While moving can easily be argued as "Material Change" even though it's Many years later, shouldn't there also be evidence of the "Impact" that material change has on the children? Obviously you know how this turned out. Yet I am hung up on the fact that the Judge's ruling never points to any "evidence" that directly shows the impact. Rather he states that the "evidence" shows that the current arrangement is interfering with the kids social lives. Again, there was no "evidence" to say the kids missed anything other than them saying they know they miss things, they just don't know exactly what they are. And even Dad could not come up with anything other than an equipment pick up day for football and a dance that the son never wanted to attend in the first place. Mom clearly tried to talk him into the dance but he was embarrassed to go (to which she did get him to go to 2 other dances months later). Unfortunately the son somehow came up with the same memory of dad's that he wanted to go to the dance and Mom said no. But no one knows when or how she was asked, they just know he was.

I know kids testimony can carry a lot of weight and for good reason. However, I also know that parental alienation goes on which we saw first hand when the kids had some crazy stories. However, are generalizations ("I don't know exactly, I just know we miss out on stuff") often used as "evidence" of impact?