I work as an SRE and while I agree with the "list of questions" as a general template for collaboration, I strongly disagree with the point that developers "own

I work as an SRE and while I agree with the "list of questions" as a general template for collaboration, I strongly disagree with the point that developers "own" the applications. If you work in the same company, you all own the application. The customers don't care that you're "only" the SRE, or "only" the sales guy. This type of attitude is toxic and should be challenged categorically. If you, the SRE, do not have the information needed (i.e. the "list of questions") then it's as much your responsibility to ask for it as it is the developers jobs to help you answer it. If you feel that the company culture makes it impossible for you to create these necessary processes so that everyone have the information they need, you need to either work towards changing that culture or get a new job.