I may be over reacting and I know that accidents happen but AIBU to be fuming with nursery? 

DH has just picked DD (2) up from nursery where he has been told that her finger got trapped in the gap between the door and it's hinges as it's shut 🤢 It was stuck and another parent had to help get her finger out. This happened as a member of staff let a child out to see their parent.
I'm so cross because there's safety equipment available to prevent this sort of thing from happening. I assumed they had it and have never noticed them not having it otherwise I would have said something.
My DH is white as a ghost because he has seen this accident happen before, only the child's finger was cut off. I couldn't imagine what I'd do if this had happened to DD.
I want to make a formal complaint so that nursery HAVE to take action to prevent this happening again and hopefully invest in hinge protectors. DH doesn't want to make a formal complaint as he doesn't want to spoil our relationship with the nursery. He thinks we should suggest to nursery they get hinge protectors instead rather than make a complaint.
AIBU?