Do not put a rivet in either of those holes. Because of insufficient (virtually non-existent) edge distance, it won't provide any useful strength, and would only tend to deform or crack if you rivet it. I think you'd be better off doing the following:
1. Enlarge your double-hole into a single larger but perfectly round clean hole. This hole will remain unused, but that way at least it won't be a major stress riser. You can fill it later if desired for cosmetic reasons.
2. Add two rivets, one on either side of the original hole, ensuring proper edge distance between holes.
That would be my general approach, but you should ask the same of Van's and defer to their advice.