Tbh I think your problem is that at 7 years old, most children are not expected to have road sense, in the sense of complete reliability at the roadside, and a 1 year delay will not be significant in terms of mobility. You wouldn't expect a 7 year old to be massively more capable than a 6 year old at the roadside: road safety is a gradual process and there is a wide range of development, so one NT 5 year old could be more safe at the road side than another 6 or 7 year old NT child.
So having said all of that, if you feel that your DD needs significantly more care, attention or supervision than most other children of her age outdoors, which is the criteria for low rate mobility, then your mobility answers really do need to highlight what it is that makes your DD's behaviour outside different or unusual to NT (neurologically typical/usually developing) children of her age, and why that behaviour means that she needs more supervision, care, or attention than children usually would of her age.
You really do need to do a dot-to-dot. For example, for DD1, one example I may give is:
DD1 has no sense of stranger danger. If a stranger approached her, she would want to be friends and would willingly comply with their wishes. It would not occur to her to question their story and she would not sense any harm that may come to her. Even if she did feel uneasy, she would not be able to excuse herself and she would not be able to get away because she is unsteady on her feet. She would not think to yell for help. Most 11 year olds have learned that they could not go with strangers, would be able to walk or run away, and would be able to shout for help.
DD1 will intend to stay safely on the pavement, but if she sees a shiny piece of paper, or an elastic band, or a pretty stone in the road, she will impulsively make a move for it, without realising that the cars on the road could kill her. As a result, DD1 needs close supervision at the roadside. Most 11 year olds would not move out onto a road with moving traffic.
Etc.