Yes, however at WDW Rider Swap is generally handled differently for a child tall-enough to enter the queue. In that situation the swap is done near boarding with all members of the party entering the queue together. A digital rider-swap return is usually only issued at WDW for a child too short to enter the queue.
And we have had the exact opposite experience. Obviously disabled adult DS who can not be left alone. Rider Switch refused, he would have to enter line and we swap inside at load ... we can't do that because DS would not understand why he can't ride after going through line.
If you use your child's DAS to enter, you should have waited only a few minutes before reaching the boarding area. If the child then decides not to ride and you get rider swap "inside the line", the adults (who COULD wait in the standby line) are essentially bypassing the standby wait. In fairness to other guests, if you don't have a lightning lane, one parent SHOULD have to wait through the standby line, so yes, you'd need to "start the line all over again".
If they get upset at the last minute, you can sometimes be gifted pixie dust by the CM if you explain what happened. They will occasionally allow you to ride, which may include a rider swap. Keep in mind this would be an exception, not the rule. If it's before that, the best thing to do is exit the line, as the rule is if the DAS holder doesn't ride, then non-DAS riders need to be in the standby line.
a think the best thing to do is if you get to the front of the line and your child dose not want to ride let the CM know your daughter is a DAS pass holder and is to scare to ride and ask them what to do.
There have been times where DH and party (sometimes me, sometimes not) have entered a queue and he was unable to ride for whatever reasons, usually his knee doesn't cooperate and he can't get into the ride vehicle. What we used to do when he qualified for the DAS was is if the ride operator doesn't know we used a DAS, we tell them as ask what we should do under such circumstances. Technically you did wait for the ride, just not in the normal queue, but again you are with the person with the DAS, so they should be riding. They have offered various solutions from a recovery pass basically to just allowing the rest of the party to ride, but we never assume and just ask what we should do and honestly there has never been a time where they have said to just leave without doing something, but they could and that would be ok to, but the point is be polite, explain the situation, be honest and let the cards fall where they may.
