If you want to file a complaint, here is a link to the South Florida Baptist Hospital with contact information:
https://baycare.org.sfbh
I have some problems with what you have written, ashleyaewing.
You said "a facial wound constitutes an envestigation [sic] from Child Protective Services" and this is not true. More is (generally) needed before CPS gets involved. If medical personnel thought the injury was suspicious, or if your son's father suggested there might be child abuse, then CPS would investigate.
The hospital examination of your son supported your claim that the bruises (contusions/wounds) were the result of an accidental injury. Why would CPS have come to your house at 2 in the morning, after it was determined by the hospital that the injury was accidental? Why would they come at 2 in the morning?
For clarification: You said you "evaluated [your] son after the accident and the time
up to the hospital visit." You were able to call the hospital before your son was seen by medical personnel, which means you were notified shortly after your son was taken to the hospital, correct? Who notified you?
For clarification: You said your son's father waited until 9pm to take your son to the hospital, "when he knew it would be difficult to do anything about it." How did you know your son was not injured again while under his father's care and this "new" injury required the hospital visit?
For clarification: You said the sheriff at the hospital "looked up" the judgment which showed you had legal custody? When and how did he do this?
I suggest you contact the hospital, if you have a complaint to make over how they handled the examination of your son. I suggest you speak to your son's father if you have a problem with how he handled the visit to the hospital. I do not see that you have much to support a legal action, though, if CPS thought there was enough to investigate. A suspicion of abuse would have allowed your son's father to have your son examined without your consent (and as the father, he would probably be allowed to take your son to the hospital without your consent anyway).
I guess I am starting to understand Proserpina's earlier post.