You can't upload any new sounds to any Roland module. However, the sounds on the module can be tweaked to an extent that they are "different" from what came loaded on it from the factory. Now, your other half can do this on his own, but you can also purchase pre-made tweaks from vexpressions.com and give these to him as a Christmas present.
Basically you go here:
The "Apex" package is the only one Vexpressions offers for the TD-11 at this time. You can download this, load it up on to a USB stick (make a copy of the file on your computer so you never lose the information) and give it to him for Christmas.