Loud, but intermittent passenger side knocking

I have a sometimes very loud and sometimes non-existent knocking coming from the passenger side of my 2018 Tacoma with 96k miles. I have 4k miles left under warranty since I bought certified used, and I've been to toyota multiple times now, even opened a claim with corporate. So far they claim they cannot recreate the sound, and that everything is normal sounding. I was finally able to bring it in while the sound was occurring and the service writer and a tech both heard it and agreed it didn't sound normal. They spent a few hours with it and told me they couldn't recreate the sound again and told me they were done and would no longer be willing to look at the truck any further. I have also found noticeable amounts of aluminum in my oil, which of course they mysteriously couldn't find when they did the oil change, but at least they covered that for free.

I am completely stumped on what this could be.i have searched the forums and not found anything that is quite the same as this and I've spent hours with a stethoscope trying to pin point the sound and the only thing I have been able to determine is that it is NOT the high pressure fuel pump, and seems to occur much more regularly and much louder when the weather is above 90 degrees. Has anyone else had a similar issue or any ideas on how to proceed?

 

That sounds worse than the usual Taco Tick