2007 IS250 AWD - Stopped accelerating on highway

My kid was driving back to school and called me in a panic because the car would not accelerate and she was in the center lane moving with traffic. Eventually, she got to the shoulder and parked it. The engine did not start after that. It wouldn’t turn over. Car had power. No smoke or steam from engine bay. No sign of oil leak under the car or at home. Recent oil change in January.

We had it towed to a shop where they did a compression test the next day and said they could not get compression in the cylinder they could “get to”. Also they noted the car was low on oil. They added 3 qts of oil. I asked the tech, if they checked codes and he said they didn’t and it didn’t matter because no compression in the cylinder. He thinks the low oil pressure caused the timing chain tensioners to loosen and the chain “fell off”. I asked if this was a fatal problem for the engine and he said it was because it’s an interference engine.

I then called my normal mechanic and he said it was a non-interference engine, but he thought the other mechanic was right about the problem.

If it’s a non-interference engine, it’s 26.8hrs of labor and $900 for the kit. If it’s an interference engine, it’s a new motor or rebuild of this one. The car has 132k on it. The body is in good shape, no accidents, new tires OEM rims, brakes, rotors, calipers, hubs.

What do you think? Is this the right diagnosis? Is it worth fixing? Does anyone know for sure whether it’s interference or not?