When are a beneficiary's rights if they feel that an executor is mishandling an estate?

You can petition the court to have the executor removed and have another executor appointed.  The grounds for removal would be fraud with regard to the executor's admission of using her sister's driver's license to obtain access to the safe deposit box.  The other actions by the executor you mentioned may also constitute fraud; sticking the beneficiaries with the costs you mentioned when the estate should be paying the funeral costs (mausoleum cleaning and flowers). The exorbitant $4000 charge for lunch also sounds suspicious.  You can demand an accounting. The missing attachment to the Will would either be negligence or possibly fraud on the part of the executor. 

Again, these items all raise serious questions about this particular executor and would be the basis for your petition to the court to have this executor removed and another executor appointed.  If this person is not replaced as executor based on her track record, there will be further problems when funds are to be distributed to the beneficiaries.