Hi, Regina!
Not to worry!
Disney Parks' new Disability Access Service (DAS) has replaced the old Guest Assistance Card, and should, in short, still enable your family to access the attractions you'd like to enjoy.
Take a look at this
Disney Parks Disability Access Service Card Fact Sheet, which includes information that relates to your question. When asked "Does the DAS Cardholder have to be present to obtain a return time at an attraction?" the answer is posted as "No. Another member of the DAS Cardholder's travel party may obtain a return time but the DAS Cardholder must board the attraction with his or her party." To me, this implies that, with four DAS Cards, your party will be able to board these attractions together, even with the additional adult support that is needed.
This informative post also directs Guests to visit Guest Relations to discuss their assistance needs. Once you've done so, I am certain that your children, their support system and you will all be able to enjoy touring the parks together; after all, that is the goal of this system. :-) Once you read a little more, I think you'll feel more comfortable that the DAS Card will work for you and your family beautifully.
Have a magical trip, Regina!
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