Hi Swan - Instead of taking the Brussels City Shuttle to CRL from Bruxelles-Midi, you can also take the connecting train there to Charleroi-Sud railwaystation. Just outside there is every half hour a shuttle to CRL, serviced by TEC, but in total it will take more time then your plan. The Brussels City Shuttle will arrive according shedule at the airport around 08:10h and the TEC shuttle around 08:45h. The advantage is that the shuttle price is included in your railwayticket, you have to indicate that clearly when buying and with €20,50 it’s cheaper then an online booked Brussels City Shuttle ticket.
As I live some 40km from Bruges I did the trip with the TEC shuttle some five years ago, because it was cheaper and I had anough time to travel to CRL. But as your schedule is so tight I think using the Brussels City Shuttle is the best option. As far as I know is Bruxelles-Midi the only place where this shuttle stops and according their website this is just outside the station. This is also the first trainstop in Brussels when coming from Bruges or Ghent. With public transport, Bruxelles-Midi remains the best place to travel further to CRL, you can’t go quicker.
Be aware that in the morning it still will be rushhour in Brussels, so some delay with the shuttle can be expected. And if you also have to drop off luggage it’s best to take anough time for this trip. You can use the option with the train to Charleroi as a back up if something goes wrong with your plan, but with this tight schedule it remains very risky. If you want to reduce the risk of a delay, staying the last night in Brussels or a hotel close to the airport is certainly worth to consider.