[1822Africa] Unable to buy recycled train across

[ChrisTheCat]

Minor 6 acquired the recycled train and used it to buy a 2 train, which is not a special train.

https://18xx.games/game/179438?action=315

Minor 4 is not offered the opportunity to buy the (not special) 2 train from Minor 6.

https://18xx.games/game/179438?action=333