In order to bill 99446-99449 your provider would have to be the provider that another one is consulting for. Here is a snip from the reference in 3M:
"The consultant should use codes 99446, 99447, 99448, 99449, 99451 to report interprofessional telephone/Internet/electronic health record consultations. An interprofessional telephone/Internet/electronic health record consultation is an assessment and management service in which a patient's treating (eg, attending or primary) physician or other qualified health care professional requests the opinion and/or treatment advice of a physician with specific specialty expertise (the consultant) to assist the treating physician or other qualified health care professional in the diagnosis and/or management of the patient's problem without patient face-to-face contact with the consultant.
The patient for whom the interprofessional telephone/Internet/electronic health record consultation is requested may be either a new patient to the consultant or an established patient with a new problem or an exacerbation of an existing problem. However, the consultant should not have seen the patient in a face-to-face encounter within the last 14 days. When the telephone/Internet/electronic health record consultation leads to a transfer of care or other face-to-face service (eg, a surgery, a hospital visit, or a scheduled office evaluation of the patient) within the next 14 days or next available appointment date of the consultant, these codes are not reported."
I don't think that your oncologist would be able to bill this as they aren't the provider that is being consulting. From what I understand from your post, your oncologists are simply putting in time to review the patient's chart, which that only is not billable.
