The reason Mark Allen wanted the Pink to be placed on the Black spot is because if the ref. decided to put the Pink on it's own spot then Marc's next shot at a red would be hampered by the Pink. Mark asked the ref. to place the device over the Pink spot again so he could have a look himself. As Mark isn't the tallest player in the world he couldn't see that far over the table so decided to climb up onto the snooker table to get a better look.
Even though the ref. decided earlier that the Pink ''Would'' re-spot Mark Allen said it wouldn't. After some more discussion between the Ref. and Mark, Mark brought his opponent to the table to have a look. Mark Davis didn't seem to bothered one way or the other and shrugged his shoulders.
In the end Mark Allen won against the ref. and the Pink ball was placed on the Black spot. Mark Allen went on to win the frame and match 5-1