Disco 2 Unknown coolant leak at the front onto the oil filter and diff

I cleaned it off and then filmed it fresh. It drips onto the front diff and oil filter, and seems to pool under an aluminum surface higher up.

I've tried to show those locations in this video (my coolant is blue):



Looking from the engine bay downwards, I can't see anything.

It's got a new water pump (maybe 3-4 months old).

Model: 4.0L V8 Discovery 2a 2003 (right hand drive, Australian)

I don't have the spanner to take off the fan, so limited what I can do at this point.