It's been more than 30 years since I computed a military travel claim.
Your answer should be available at
051003. Service Member on Active Duty who Retires, is Placed on the TDRL, is Discharged with Severance or Separation Pay, or is Involuntarily Released with Readjustment or Separation Pay and Associated Dependent Travel ...
at
LINK <--- and pages starting at
5B-35
Offhand...the retiree and the dependents do not have to travel at the same time.
If I remember correctly, the distance allowed is to the home he/she selects (which one can choose currently) or place entered active duty. This should be confirmed by reviewing the Joint Travel Regulations which are cited above.
I would have to re-educate myself in travel computations to offer comments regarding amounts of reimbursement.
Good luck,
Ron