Beats me. I tried to destroy a TG with a fighter in ( using delete TG from F12 window ), and the Squadron details ( in F7 window ) immediately updated no longer showing that fighter... :/
Now I cant deselect fighters to leave their squadron... So in the end I launched them and destroyed them in task force menue... But they are still in Fighter squadrons (F7).. How do I delete them from there??
Did you make sure to have the correct mothership selected in dropdown when trying to launch from fighter squadron interface? ( I always miss that myself ).