Hi Everyone, just purchased my first Porsche. Its a 2016 Cayenne GTS with 65k miles. It has the 3.6l TT, air suspension. In SoCal

Unfortunately, I had a breakdown before I even got home as the tensioner pulley broke off and shredded the belt. I was able to find the parts and fix it in a parking lot. Having this experience, I have a few questions I was hoping to get answers from people in the know

1. I was having a hard time identifying which engine I have. Is it the same engine as the Cayenne S, but tuned different? Is there a cross reference rule of that that will let me use parts from other engines?
- 1a. Even when I entered my VIN in Gaudin or Sunset Porsche, the schematic on the belt diagram was wrong.
2. Anywhere I can find out of my model has certain known points of failure? For example certain aluminum bolts breaking off (and suggested to replace with steel), or certain bolts backing out (and suggested to take them out and re-torque with blue locktite.
3. My transfer case has been replaced 5k ago. It was the "new" design (not sure what that means as this seems to still be an issue with new cars?) Not in warranty anymore. Outside of changing the fluid every 10k, is there anything else to help? Ive heard slow driving isnt good for it (or maybe that was PDK), so when in traffic you should either stop or drive, but not slowly crawl with occasional gas input. Is this true? anything else?
4. I will be looking for an indy mechanic, but I am a DIYer, and would like to think I can do the basics such as oil changes (Transfer case fluid), brakes, spark plugs/coils, etc. However, this is German and I am not familiar with the nuances.
-4a. Will I need the Launch x431 proMini to do anything? Is there a better unit? (I also have a 2005 Mini Cooper S)
5. Parts - Drive belt was difficult to identify and then source same day Not even all the dealers had them, which was hard to beleive. I bought it from the dealer. Tensioner pulley I bought from Pelican Parts
-5a. What parts brands are deemed OEM or better quality? aka do we know which parts manufacturers supply Porsche?
-5b. Is there a VW/Audi cross reference guide?
-5c. Are there any in addition to FCP Euro, Pelican Parts (Local but a difficult drive)? Certain brands from RockAuto acceptable?
6. Turbo. From what Ive discovered, the turbos are Turbo Compounding units. I know some semi trucks use them and frankly, they seem to have a higher fail rate with a catastrophic engine failure when the bull gear explodes, sends metal into the oil pan, picked up and spreading the shavings throughout the engine.
-6a. Is this a thing here?
-6b. The best prevention is more frequent oil changes (semi mfg has a recommendation of 60k, but that is waayy to long, imo should be 20-30k). Porsches 10k seems to be too extended. Do people generally change oil at 7.5k, 5k, or even 3k?

Anything else I missed? Id prefer to do all the major maintenance in the near future and not have to worry about anything for the next 50-80k miles.

Thanks in advance for any help!