I quit my job and still havent gotten paid for my remaining PTO time. The administrator at the time said they would be sending me a seperate check for the PTO but she has since left the job and the new administrator says because I quit my job without notice I may have forfeit my rights to the PTO and wont get it. Can they do this??

They can if the policy provides for it. Vacation in Nevada (and most other states) is not unconditionally vested. However, if the policy states that accrued vacation is due at termination, and does not contain a forfeiture clause (such as the one the new administrator conveyed to you), then the state does consider such accrued vacation wages, and it was due no later than 7 days following your last day worked.