If there are 2 POA's listed on a will and 1 of the POA dies does the inheritance go to the remaining POA in full?

To answer your quesiton, we need to address what "POA" means.  It stands for Power of Attorney.  While your Aunt is living, she can name someone as a power of attorney to handle her legal affairs (sign contracts, talk to the bank, untility company, etc on her behalf), but that power only exists while your Aunt is alive.  The POA is not a Last Will and Testament.  The POA does not control who inherits.  When your Aunt dies, the POA ceases to have power.  Normally, you only give a POA to someone you trust completely, because they have complete power over everything you own.  Neither your cousin or your Dad have any right to inherit based only on a POA.   If your Aunt prepared a Last Will and Testament ("Will"), then the Will governs who will inherit.  If your Aunt did not prepare a Will, then her property would go to her next of kin according to the order listed in the state statutes.  (Spouse, children, siblings and so forth). I would need to review any documents you are speaking of to be sure what legal rights exist.