OK, well if
DAS has been denied and the recommendation was to use a mobility device, it may be something to consider. If walking is the challenging and an
ECV is too expensive, maybe a wheelchair? Or if it's more a need to sit occasionally, maybe a rollator (walker with a seat) or a cane seat.
Attraction Queue Re-entry might work -- where part of the party stays in the queue and the individual who needs to attend to their disability steps out and rejoins via the LL.
PP suggested stacking G+ and ILL$. Yes, those are "optional" services but if it helps you have a more enjoyable vacation it might be money well spent, especially if the sole intent is to less time in the physical queue those are the options for anybody who truly desires less time in the queue. "Extra cost" is not necessarily something that comes into the equation of determining who qualifies for an accommodation, though obviously it is an impact on the individual and something you would need to decide your budget can manage. Maybe a couple of QS meals instead of TS during the trip can offset the cost.
Does the jetlag last the full 2-weeks of vacation? If it's better after a few days maybe plan your park visits to be heavier on the latter part of the 2-weeks and plan more resort time in the first few days. If the jet lag does last the full visit, I guess that is a personal decision; I don't know that I could enjoy a 2-week vacation if I was exhausted from jetlag the whole time.