I don't think keeping photos inside an envelope is the issue. I kept all photos in the studio envelope. It's all about arranging documents in the order they are asking for, make it easy for them to review. Provide supportive documents for each entry in the application.Thanks!
It's only his parents and brother. They've now been listed on the Additional Family Information page. We have the 2 recent photos, we've made them visible instead of in the photographers envelope. Thought it would be common sense. But hey! It appears to be all correct now, I've triple checked. There shouldn't be any issues past this.
By the way, best of luck with the current application.