First, the issue is, where do the Catholics find a biblical justification for the veneration of saints. The question is not whether interpretations of these verses exist that are not Catohlic.
Second, for your interpretation to even make sense you have to explain why these prayers (Apoc 5 and 8) are delivered to God by saints at the Judgement day if they are not connected to the people being judged.
I'm not saying the prayers are not connected to the people being judged. I'm saying the saints are not "physically" delivering the prayers in the first place. The prayers from those being judged go directly from them to God, no middlesaints.