FED DH Question

[Tim C]

The following situation was sent to the PBUA today for clarification:

1- Able #25 (4)
2- Baker #33 (7)
3- Charles #41 (2)
4- David #51 (1)
5- Earl #27 (6)
6- Frank #3 (3)
7- George #21 (9)
8- Thomas #7 DH for George
9- Herman #14 (8)
10-Issac #40 (5)

In the top of the 4th inning sub Anderson goes into play RF in place of George.

Coach says that, "George will move to DH"

Umpire says, "Coach you can't change the Space Time Continueum -- this isn't an episode of Star Trek!"

Coach scratches head!

Please post your answer and all notes that support your decision. Can this legally happen or not?

"Play on, mates!"