Expansion and contraction of conduit should be dealt with independant of the expansion and contraction of a concrete tilt up wall corner............think of it this way, the north&south walls will expand/contract east and west,the east&west walls will expand/contract north and south but they will act differently than an integral pour corner.A lot of stresses will occur at the corners of this type structure if the temps are extreme.I would ask the comtractor to look at the civil/architectural general specifications and see if it is covered there.
I would not look back ,I would install the expansion joint and get on with it.
JMO,dick