I ordered this one;
https://www.ebay.com/itm/153769766639
If I remember correctly, I had a LockSmith Program it, with his Programmer, and it worked.
However, it didn't fit the FlipKey Case, so I had to buy an OEM Transmitter (to fit the FlipKey Case).
I think there are only (4) RF Remote Slots, so I gave up that eBay Tx's, Slot for the OEM Transmitter.
In total I have:
(2) OEM Square Tx/Key [CWTWBU745],
(1) OEM Pentagon Tx/Key [CWTWBU766] in Flip Case,
(1) Original Tx w/ Separate Key [NHVWB1U711]
I had to clone some Transponders to get all (4) Keys to start the car.
I think only (2) Transponder Slots are allowed.
Your problem might be trying to program the Tx yourself, as the Locksmiths Machine makes it much easier.