"Reuter's impossible timeline" has been verified by other sources.

Other sources? Name them, if they are press sources then they as ill-informed as to the set up and operation of a BOP Stack as your Sri Lankan friend "who worked on rigs".

Just a logical question taking into account this "verified timeline". IF there was a fire and an explosion on the Deepwater Horizon on the 20th of April, and the Deepwater Horizon itself sank two days later on the 22nd of April, who and what determined that the BOP failed on the 25th of April? Who and what was there to monitor it?

NOW READ THIS

How A Blow Out Preventer Works For Dummies

Relevant piece of information from above:

During the Deepwater Horizon drilling rig explosion incident on April 20, 2010, the blowout preventer should have been activated automatically, cutting the drillstring and sealing the well to preclude a blowout and subsequent oil spill in the Gulf of Mexico, but it failed to fully engage. Underwater robots (ROVs) later were used to manually trigger the blind shear ram blind shear ram preventer, to no avail.

As of May 2010[update] it is unknown why the blowout preventer failed.

Now as to the situation at the time of the blow out:

At the time of the explosion, it was drilling an exploratory well at a water depth of approximately 5,000 feet (1,500 m) in the Macondo Prospect, located in the Mississippi Canyon Block 252 of the Gulf of Mexico in the United States exclusive economic zone about 41 miles (66 km) off the Louisiana coast.

Production casing was being installed and cemented by Halliburton Energy Services. Once the cementing was complete, the well would have been tested for integrity and a cement plug set, after which no further activities would take place until the well was later activated as a subsea producer

Then we have this from Don Firth who knows the square root of fuck all about offshore drilling:

The FIRST bore-hole was going well until the BP manager insisted that the Deepwater Horizon crew "bump up" the drilling—which the drilling crew knew to be unsafe. Yet, at BP's insistence (and threats of being sacked), they did speed up the drilling.

And what they feared, happened. But fortunately, no blow-out occured with THAT hole.

But they had to abandon that bore-hole and start another.

And that's the hole where everything went wrong and the blow-out occured!

If the crew had been allowed to complete the first bore-hole at a reasonable pace, and hence, safely, the second hole would not have been necessary.

Complete and utter load of crap. The rig was engaged in setting production casing every bloody report tells you that so drilling had been successfully completed, because you cannot set casing with the drill string still in the hole. They had actually started cementing so they had even completed running the casing. Drilling and the speed of drilling has, got and never did have any connection to the blow out.

The cement job failed (Haliburton responsible), the BOP failed (Cameron/Transocean responsible depending upon who owned the piece of equipment), THEN there was the fire and the explosion.