2011 Ford Flex 3.5l V6 start issue, lean codes stored?

Customer states vehicle lost power, check engine light came on, heard rattling sound. Now it won't start.

Checked all the basics. There are codes stored for bank 1 and bank 2 lean, and bank 1 and bank 2 02 sensor codes "biased lean" I did a smoke test with the throttle body open, didn't see any intake leaks. Therefore suspect a fuel delivery issue. However, this car does not appear to have any schrader valves and doesn't have any fuel pressure PIDS. It also has a low and high pressure fuel pump. Looking for any advice to go from here (rookie tech.) If curious, I think the engine 'rattled' from being lean and causing preignition.

Added (1). Car has 140k miles on it

Added (2). It does intermittently run (has once) enough to drive around the parking lot, then it dies again. I'm positive its not a spark or compression issue

Added (3). Also, when it did run, it sounded like it was running great with no issue

Check for basics (mine). No starts are the easiest thing to diagnose. Does it sound like it has compression when you turn it over? Does it have spark - pull a coil pack and jam a grounded plug in it? Does it run if you shoot aerosol carb cleaner into the throttle body?

OK, agreed, not a compression issue but you have a gift right now, it's not running, so find out why. Spark or fuel? No agreement on the spark issue until you confirm it and if spraying carb clean into it brings it alive you know you have a fuel supply problem

LOOK FOR A VACUUM LEAK.