So, the vibes I get:
Flat Earth Man is the villain - or maybe just the secondary human antagonist? - of a children's movie, a corrupt land developer who wants to raze a beloved if rundown and unprofitable local observatory and astronomy communications facility to build some ugly mall or something. While he may surround himself with the tools of the trade, the trappings of expertise and the costume of business sophistication, he is just an igonrant fratbro jock nepo baby - after all, there are no flat earth surveyors.
Glober is the lovable dork running the observatory and one of the heroes' adult allies. In college, Flat Earth Man was his bully and sabotaged Glober so he was unable to join NASA, leading to his unappreciated job. He may be the flawed but good-natured single father of one of the protagonists, struggling with the loss of his wife.
In the end, Flat Earth Man is foiled and disgraced, the observatory is revitalised, Glober gets character development, gets respect - possibly graciously rejecting an offer of a high-ranking NASA job after thwarting an alien invasion, having come to truly appreciate his position as a humble local science communicator - and gets the single mom.