There may be another possibility...
And though it's pretty cliche sounding, and the anime already tried it.... there still is a possible separation of Moka. But it may not come in the form one would think.
Imagine, Fuhai fixes the seal, but there is a tweak to it that would modify the seal slightly. This tweek would still seal Moka back into her dormant state, but at the same time allow her to step forth... and would work on Moka in both her sealed and unsealed states... It would allow both of her to remain conscious... and she would be allowed to communicate at any time with the outside world...