chicken and veggies, different temps, what to do?

Please excuse what I'm sure is a very basic question- I am making dinner for my mom's bday tomorrow, and will be making boursin-stuffed chicken breasts and roasting cauliflower. The chicken is to be pan-seared first, and then baked in a 375 oven. The cauliflower is to be roasted at 400.

I don't think the cauliflower will come out right at anything less than 400, but will it ruin the chicken to cook it at 400?

If it's not a convection oven, it'll be hotter at the top than the bottom (at least my oven is.) Try the cauliflower on the top rack, with the bird on the bottom.

Seems to me that 25 degrees will not make a significant difference to quality as long as you monitor it since it will be done faster.