Chinese US green card holder

You can't get a Macau visa as there is no such law in its books. Legally you can only visit Macau with a Two-way Permit and an entry endorsement, both obtainable from the Exit and Entry Administration of where your hukou is. Using a Chinese passport requires you to be in transit to a third country other than HK as well as an onward ticket.

Keep in mind that you don't need to actually go to the third country but simply need to have a ticket, which can be easily obtained in Gongbei/Hengqin for a couple hundred Yuan. Chinese immigration will only let you through after verifying the ticket.