I can get the loft to not fail by making sure the two profile sketches do not coincide at the z-axis (maybe you've already tried that): -
The vertical edge of one profile is offset from the axis by a tiny amount in the above image. Not exactly what you're after.
Maybe it's something to do with the two profiles 'sharing an edge' so cannot loft correctly?
Even then, it doesn't look like the profiles have 'matched-up'. Maybe more guide curves needed?