Manually configure light bounds? / Optimising lighting for dynamic batching

Here's the quick background, my project has:
- Lots of dynamic objects
- 4 dynamic lights
- Mobile/VertexLit shader
- Targetting Android

All the dynamic objects are sharing a single material, so I'm relying on Unity's dynamic batching to bring the draw calls down to a sensible amount on Android. And in theory, Mobile/VertexLit can do 4 lights simultaneously (via vector ops) so this can all be done via a single draw call.

Problem: Since the lights all cover different areas, some objects fall under light 1, some under 1+2, some under 3, some under 3+4, etc. etc.

Unity (in it's infinite wisdom) is trying to make dynamic batches for each combination of lights, which means in my test scene, 6 objects each fall under a different lighting permutation and end up as 6 batches (bad!). Really, I want to (somehow) force Unity to only consider one lighting permutation (all 4 lights) and then create one dynamic batch for this, so all 6 objects become one dynamic batch.

Ways I can think of doing this:
1. Somehow force the light bounds to be huge, so that Unity thinks all objects are lit by all lights.
2. Disable light culling for dynamic batch generation somehow
3. Mess with my object's bounds so that they appear to be intersecting all of the lights (but will this then mess up frustum culling?)
4. Ditch Unity lighting and write my own shaders (ugh. super time sink).
5. Something else.

Unfortunately, I do not know how to actually do any of these in Unity, as it appears I can't dig deep enough into the renderer. Anyone any suggestions? Thanks.