Malcolm, maybe so, but the shipowners these days won't pay for a berth, they don't need a drydock, seems the tug is bringing the parts required and Wartsilia/Sulzer people to fit them, all of which can be done at anchor. They will need a new crankcase door for a start and possibly a bearing, though they should have a Lloyds spare on board.
This will be an insurance job with P&I involved, so they might as well have the experts carry out the work, rather than ship's staff of dubious competence.
Assuming it was a crankcase explosion, as it said an engine explosion and fire, this is caused by a part in the engine becoming too hot for any number of reasons, this changes the oil vapour temperature in the crankcase until it reaches its explosive limit and bang.
There are large mushroom type relief valves on each crankcase door, usualy starboard side about 1 meter diameter, which will open with the increase in pressure, but at some point fresh air will enter and you get a secondary explosion that causes the fire.
These explosions are quite rare but if they happen can be disasterous.
Rags often drop in the crankcase from Engineers pockets, eventually end up in the suction strainer of the lube oil pump, this limits the oil flow and a drop in pressure, if this is not noticed then the engine is starved of oil especially when the ship is rolling, trim affects the lube oil level also, chief engineers don't like to add too much oil to the crankcase, as this goes down as useage and they are questioned. Sludge often settles in the bottom of the lube oil tank and in heavy weather is disturbed and the pump picks it up.
This ship is 21 years old, with various owners and the more owners the less they want to spend money on an old ship. So its the slippery slope to scrapping or a disaster.
It may be called Mearsk .......... but may not be owned by them but sold and charted back such that they are not responsible for the ship.
This seems quite common these days.