You could possibly use a bulb as a stand-in, similar to how a canary bulb used in the power outage smart app.
The problem is that a zigbee device can only belong to one coordinator. So you would have to have the bulb and the remote both on the smartthings network, and I’m afraid you would then have the same problem with the remote dropping off all the time. At that point I don’t think it can still control the bulb.
You can definitely have a device respond as though it is a bulb, which is basically what the Wink hub does with this device, but smartthings would have to modify the hub’s firmware to do that, and I think that’s very unlikely.
So good ideas, but I’m not sure they’d actually work in practice. Well, I’m sure that modifying the hub’s responses would work, it just doesn’t seem like that’s something smartthings is going to do or they would’ve done it already.