Lots of problems here, including ships too big for waterway.
The Afran Stream was 130,000 dwt.
One source says the Vic Bilh was a 100,000 dwt,
but we need confirmation.
But perhaps the prime cause
is the poor low speed maneuverability of single screw tankers.
For these ships, minimum steerage way is about
6 knots even in open water.
And if you stop the prop to take speed off,
mimimum steerage way is more than 6 knots.