This sounds way beyond a bit of shoving...
So this ex convict... (this is important; the best predictor of further law breaking is previous law breaking-some go straight, most don't. ), attacked your husband, from a height, and tried to gouge his eye out?
And had to be pulled off your husband??
Surely this is GBH /attempted? Lawyers help me out?
Can completely see why he is worried. Can you ring the police for a chat? , you don't even have to give your details... Just outline the situation and the fact that you're concerned re further assault/repercussions?
I hope your husband won't go back while this thug is still around.
Do you know if this bloke has history of drug /alcohol issues/severe mental health issues?
Unprovoked attacks are pretty rare... Although the ex prison history are important.
Assuming prison history is violence related? And the fact he's threatened others is important too.