Certified GKH Gardening Expert
Here is a link to an article that may be of help to you: https://www.gardeningknowhow.com/plant-problems/environmental/treating-leaf-gall-on-plants.htm
There are times when the newly unfolding leaves have been damaged in some way while in the leaf bud stage and as they unfold they may have little bumps or fold lines on them. Always check the underside of such leaves and see if there is anything lurking there or
any signs of some insect having taken a bite out of the under leaf material. It can take using a magnifying glass to see some of the little culprits well. The rose leaves turning black is a sign of some sort of foliage damage from evening cold temps frost, chemical overspray or perhaps something that got into the soils of the rosebushes and thus got taken up by the root system.