Wind plays an important role in plant growth and transpiration, but I think a lot of people are making their grows too windy.
Think of it like getting out of a pool on a windy day versus a still day. You’ll still dry off in the sun, but at a different rate. The more wind, the faster the leaves can “dry off” by transpiring. What that means is they move a lot more water through them on a windy day than a still one. If your nutrients are strong and the plants are transpiring hard it can lead to nute burn and having to flush. Seems unnatural, but running a weaker nutrient solution during fast growth can actually work better than a more concentrated one.
I guess my point is that you can grow great plants with a little or a lot of wind.
As far as mounting it, can you use one of the roof crossbars on the side? If the fan is mounted so it pulls against the bar it might make things feel more solid.