Welcome to the board RBQ, sorry you are here with a problem. This is fine, if the moderators feel it should be moved they will. You are certainly welcome to post pictures of your own projects. We just changed formats here and some people are still having problems posting, we have a good help section for board issues:
https://www.quiltingboard.com/qb-help-center-f27/
So no, the squares should not have separated under normal machine washing and drying. That we piece together sections for a border is not unusual. It can be done in various ways, sometimes as quilters we have a design sense of adding in a bit of "pop" or something that might not be so appreciated by someone else.
To make sure I understand you sent someone the blankets and they sent you a completed quilt? In that case I would approach it by calling the quilter and saying "Hey, I got the quilt but when I washed it, this happened -- is there anything you can do to fix it?" or sending an email with pictures attached. Then see what they say. They should stand behind their workmanship and apologize and do something. If they shrug and say "your wash/your problem" then it is most likely not worth fighting over (depending on the cost). But we can maybe figure out was for you to fix it.
It's one of the dis/advantages of making the entire quilt yourself, no one to complain to but yourself if you don't like the workmanship. If you made the top, it's not up to the quilter to fix the issues you put in.