Can a office keep credit card number of file to charge me in the event that my insurance company pay him within 30 days and then reimburse when he finally receives payment?

It depends on the specific circumstances and policies of the office and the insurance company. Some offices may have a policy of keeping credit card information on file for such purposes, while others may not. It is recommended to directly inquire with the office about their specific policies and procedures regarding payment and reimbursement.