Just watched this episode and dont worry that mother was in on it all the time IMO
The mothers outfit matched exactly with the colour theme, IMO all of them had decided that the colour would be the same as the Landrover
As for the cupcake wedding cake it was highly suspicious that the wedding cup cakes we decorated the same as the ones in the brides mothers house
As for the wedding dress, suprise suprise both the bride and MOB loved his choice after the MOB was so pernickety about her DIAMONTES
IMO they gave him orders on where to go, who to book and exactly what to do before the wedding
It was all just to convenient that everything fell into place