Wet is a wise woman :)
I'm sorry to have unsettled you. My friend did she same things as you; she visited other mainstream schools, schools with asd units, asd schools which he was too HF for. She then visited an EBD school which she had good vibes about.
If you feel good about the school you have asked for, your instincts are probably right.
My friend on the whole does not regret sending her ds to an EBD school in Y1: he had learned some violent avoidant behaviour during Reception before being excluded. While at home he sunk into depression and became almost agoraphobic. He was on meds for depression, ADHD and insomnia.
When he started at his new school, he hated schools. His school managed to control his outbursts and he started settling down. After a year, he actually liked school, and stayed for after school clubs and went for weekend activities!
The staff are great, but as the children get older, staff have expectations that they have learned certain behaviours. They are not making allowances for his PDA, and even with an official dx say "some doctors" believe it exists
. Eg they believe if you are given a task, you must finish it. For a child with PDA, such a demand would create unbearable anxiety.
My friend is struggling to find another placement, and there are few at primary level which would be suitable, and far away. A specialist residential would probably be the only real option.
I think you need to go with your gut feelings. You clearly felt the school you asked for could work. As it appears to be the only choice, it may well be worth taking up; but as [Wet] said, watch, monitor and record.
Best of luck 