I need help and you take a cake that is frozen thaw it decorate it put it in the refrigerator for a couple of days and then put it back in the freezer? I made a cake for a friend they then said they couldn't pick it up right away so I refrigerated it. Then they said the event was delayed to freeze it. How will that affect the cake.
As long as it's wrapped up good, it shouldn't negatively effect it at all.
My opinion is that you should never re-freeze something that has already been frozen and thawed out - something in the recesses of my mind about food hygiene. If you were decorating in fondant and froze this it would affect the fondant when it thaws, colours and bleed and fondant can crack when dry. If these people booked the cake for a specific date then they need to honour that or place it in their own freezer.
Wrap it tightly and freeze. If there is lots of fondant on it, also put in a box and wrap the box with plastic. When ready to deliver, unwrap and let it come to room temp slowly. the fondant will be sticky at first but then it will dry. I had to do this once. It was fine.
Wholesale bakeries do it all the time. Cakes go from the oven to the freezer, from the freezer to the decorators while they are thawing, packaged, refrozen, and shipped.