No, it doesn’t.
It has two ANALOG inputs.
The only digital “input” on the xCAN is via Bluetooth.
Using a balanced electrical connection, i.e. as AES/EBU, in the digital domain has absolutely nothing to do with getting balanced input or output from an audio perspective. All that does is give you a more robust S/PDIF (technically AES3) interface. It’s still just a bi-phase clocked bit-stream and has no knowledge, nor control, over how that data is converted to analog audio - nor any influence or relevant as to whether the analog output of the DAC (which is all that matters for the xCAN) is balanced or not.
If what you’re wanting is a way to connect the Lightning output to the AES/EBU input on your Theta, you’ll need a USB digital-to-digital converter (DDC), of which there are many options (Singxer SU-1, Schiit Eitr and many others).
You’d use the Apple Lighting to USB-3 Adapter cable to connect a USB cable to the iPhone, and then plug the other end into the DDC, and then the DDC would connect to your Theta Casablanca.
In the case of the Singxer SU-1 it has an actual AES/EBU connector on it, so you just need a AES/EBU Digital cable. With the Eitr you can either use it’s RCA-COAX S/PDIF output directly into an S/PDIF input on your Theta, or if you really want to use the AES/EBU input you’ll need to add an RCA-COAX 75 OHM to AES-EBU 110 ohm Balun (transformer) as well.
The ONLY connections you can make to the xCAN, regardless of your source, are either analog (2.5mm Bal, 3.5mm Bal or SE), or via Bluetooth. Which is why the options I listed all involve using a cable that has a built-in DAC to give you that analog output that the xCAN needs.
The short version is that the xCAN is an amplifier, which is an analog device, and the only “digital” input it can take is via Bluetooth.
If your sources are simply the iPhone and Macbook, then absent driving some very demanding headphones, and already have a DAC, you really wanted the xDSD.
From what you’re asking, I don’t see how the xCAN is useful for you unless you have analog inputs to feed it (since you say you aren’t using Bluetooth) and need more power than the xDSD can deliver into headphones.