I just got an AP last week and I notice about the same, once its up to temp they vary but are usually within a few degrees.I watched again and maybe a mix difference of about 10*F during warmup and within 5 once warmed up. During warmup the gauge cluster was always lower than AP reading. A few times after some pulls the AP would read cooler than gauge cluster.
I looked thru that SSP manual or whatever and it only shows a single oil temp temp sensor located in the oil pan. So for now my best guess again is that the gauge cluster reading is simply delayed / averaged out over time vs AP which is probably reading direct from the sensor. This is on a 2017 Audi S3, might be a little different for the VWs, but who knows.