According to matrix.itasoftware.com here are the taxes on a roundtrip BRU/DKR:

Belgium Passenger Service and Security Charge (BE) €27.38
Senegal Immigration User Fee (VH) €9.27
SN YQ surcharge (YQ) €294.00
Senegal Passenger Service Charge (ZE) €24.40
Senegal Passenger Security Charge (DF) €6.10
Senegal Infrastructure Development Charge (HP) €54.00
Senegal Civil Aviation Charge (KQ) €2.29
Senegal Immigration User Fee (VH) €9.27

Looks like either your tax list or Brussels Airlines tax list is outdated.