Toyota definitely does not cover replacing both sides under warranty. Your dealer must have had an extremely good warranty clerk. Hubs and shocks do not get replaced in pairs under warranty; I've seen countless cars return to the dealer for replacements under warranty and they have never been done in pairs - under 3/36 or under Extra Care.
Hate to say it, but your training was incorrect. The advice to replace in pairs may be applicable in high-mileage examples for customer-pay repairs, but definitely not for warranty.
Also, I referenced the Toyota and FCA service info earlier and neither source states to replace these components in pairs.
Oddly enough, FCA only sells the gasket and the oil filter adapter/warm assembly together. No joke.
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Contractually, FCA warranty states that warranty repairs must be performed using new or remanufactured parts. Removing a component from an inventory new vehicle that has not been titled is a serious grey area. I have a friend at a different automaker and they have been warned to avoid this option since the automaker is potentially violating its warranty service agreement.