Hi Alison,
It is extremely unfortunate that it happened to Malaysian airlines twice, and it's a very rare occurrence when you consider how many flights there are around the world daily!
With regards to booking your own flights, you can do - however, you will not be able to get a discount from Just You. This is down to the fact we sell our holidays as a package and we cannot separate these components of the tour.
If you need help with booking flights to meet with the itinerary of the tour or if you need any other information, you can call one of our friendly holiday specialists and they will be happy to help.
Kindest Regards,
Monty