It is a hard lesson to learn but you saw the warning and ignored it. No Engine I know of will last long with extremely low/no Oil Pressure at high rpms.

If you have Oil in the Pan it could be the Oil Pump Drive Failed (Chain, Chain Tensioner or Gears) or something happend inside of the Oil Pump to the Pressure Relief Valve or spring (I have read of problems in this areas on this forum).

If misery loves company; in the past I tried to solder the Seam on a Radiator Tank; only to have the Seam open up on the Freeway in heavy traffic.
By the time I got it off of the Freeway it was too late and I had that Knock also; due to wiped out bearings.
The good thing is it was not a Mercedes.

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84 300D, 82 Volvo 244Gl Diesel