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DDP has no meaning at all as far as making restaurant reservations, except at the four prepaid restaurants (CRT and the 3 dinner shows). THe plan is only a method of payment, and except for the prepaid reservations it doesn't enter into things until you arrive at the restaurant and use it to pay. This doesn't really relate to the dining plan, so I'm moving it to the Reservations board.
The online reservation system does not allow one guest to hold concurrent reservations within an hour or two of each other.
To make these reservations under the same name at 180 + 10 on your resort reservation, you may need to call 407-WDW-DINE.
If you are within your 180 days and not using 180 + 10, just have different persons make the reservations.
If you have one reservation at Teppan Edo while the others do counter service, none of this matters, because you do not make reservations for counter service, so there will be only one reservation at that time.