Cyclists are on the left most of the time. Also, large vehicles do not turn left directly from the left-turning lane, they move out to the right before turning which would make passing on the outside just as hazardous.
Cyclists are not always killed as they filter up the inside, they have been killed by lorries that overtake and then turn, by lorries that pull up along side them at the lights and then turn, by lorries that fail to give enough room when both are going straight on and by lorries pulling out of side roads.
If the design of the cab means that the drivers cannot see cyclists then they should not be used on any roads where there are cyclists. If they must be used on such roads then the cab should be redesigned, one like that on the old-style routemaster bus would give the driver a much better field of view all round.