The park is ok, I think it's the perception rather than the reality.
Things happen everywhere we go, and given the number of people who use the park I think incidents are fairly rare, from the sounds of this one it would appear that they knew each other and the park was just an incidental location.
I would (have, and do) quite happily walk through there at any time of the day or night, then again I've done the same thing through Delamere Forest since I was 9 (maybe 10), although I think my current position of walking with a "wolf on a string" would make even the most desparate think twice before approaching out of the darkness