Try this trick. Turn the bars so the clutch master cylinder is the highest point in the system. Squeeze the lever close to the bars, then wrap a bungee cord or Velcro strap around it so it holds the system under pressure. Leave it like that overnight.
No promises but sometimes this will force the air bubble to the top where it can bleed out to the reservoir. Good luck. Let us know if this works for you too.
You already know the fan runs with DC applied to the fan.
If you can use a volt meter, test for voltage at the fan using AC (alternating current) and DC (direct current) scales. It should be DC. Of course, the bike should be at temp so the thermo switch is on.
If you are not familiar with a volt meter, you could also simply connect a 12 volt light bulb in place of the fan. If it lights, you have power. The bulb will light with either AC or DC.
If DC, the fan should work. If AC, the fan will not work. The rectifier is what converts AC to DC power. So, if you find AC power, replace the rectifier and you should be back riding.
thats_a_five's post in Spongy Clutch Seems Impossible To Bleed Wth was marked as the answer