Sorry in advance for the long post.
My check engine light in my 2001 Camry 4cyl recently came on with code P1135. Google shows that this is usually a faulty sensor. However, I noticed on some posts that the problem actually ended up being the flex pipe. On my last oil change, I went to a shop that told me I needed my flex pipe & tie rods replaced so I am inclined to think that it is the problem. However, I can't see any obvious holes and it doesn't appear to be making the typical "fart" noises that are from a broken pipe. Also, the shop tried to tell me that my engine needed premium fuel because it's "cleaner" (didn't trust the flex pipe advice after they said that).
What are the odds that it is the flex pipe or the sensor? And is it safe to continue driving on it? I have a trusted shop that I want to go to in my hometown (that doesn't try to sell me premium fuel), but I am currently over 100 miles away.
I have attached pictures from the shop before the cel came on and a video of me looking for a leak but not seeing one.
Also, I have never done my own repairs before and don't have much besides basic tools. Am I right in assuming that a flex pipe repair would be too much? Looks hard without a lift from what I see on YouTube. On the other hand a sensor replacement doesn't seem difficult.
Finally, the app I used to check the cel showed "errors" in other areas but no code and google wasn't very helpful on this. Any advice on this?