LGW-GVA 21-28 Jan 2023 spare ticket (£100)

We have a booking with BA for 4 people. Details are as follows:

Gatwick to Geneva: 21 Jan 2023 at 14:50 landing at 17:30

Geneva to Gatwick: 28 Jan 2023 at 14:05 landing at 14:50

One in the group cannot make it and BA won't let us cancel her ticket. However, BA allows me to change the name of the fourth passenger for £100.

The big plus is that my luggage allowance is huge. I believe I can check in 8 bags of 32kg each. I do not think we will have more than 3 so the rest are available and you can also bring a cabin bag, a backpack and join us in the BA lounge.