About the only thing I see that might be connected or related to the oil system is the oil pressure sensor.
It may be covered by the starter and hard to access.
What you have to do is let the engine cool down and then get in there with a bright light and perhaps a mirror to pinpoint the leak. I know it is hard to do with clean oil, which can be hard to see, but that is the beginning process. We have used dye that is put in the oil to make it easier to find the source of the leak, but I would think if you have a large leak, it would be easier to find.
I know it is messy, but it might be best and easiest to get a look under the van with a really bright light and then start it up for a few seconds to see if you can spot the leak. Of course this should only be done is a safe manor. It should really be up on a lift, in Park, and the wheels blocked. Do not put yourself or anyone else in danger.
I would still consider that the oil filter may not be sealing well and the oil is "squirting out" from around the seal and it is hitting the engine in that location.
Please let me know what you find.
Take Care, Greg A.