Sorry to hear this. Just wondering which country you are from? I mean any such case where sugars are so high and patient being symptomatic (1 episode of passing out) is considered emergency in any country. You should not wait for him to start on treatment on anti-hyperglycemic treatment for 1 more week. Take him to the Emergency Room of the hospital where his doctor would be seeing him. Make sure he's started on treatment by medics for such a high sugars right away.
Yes, this could be new onset diabetes
which went unrecognized till the sugars jumped this high. In case he is on any steroid
medications for any other condition then that gives him such high sugars just temporarily and we do not call it diabetes.
Irrespective of the diagnosis, please keep it in mind that initial treatment with insulin
or any other antidiabetes medication has to be started right away.