Does he have a candidate (other than "none of the above")?

As a Head of Government he has such right to oppose some candidatures. Fractions and HoGs choosing candidates for Commission President are two separate things - for example Viktor Orban from Hungary is also opposing Juncker candidature but his party is in EPP. For you as radical left supporter that should be better when those parties from Denmark and Finland will be part of eurorealist/euroconservative ECR than theoretical Le Pen fraction.  

_________________________________________________________________________________ Christus vincit, Christus regnat, Christus imperat

I just found on EAF wiki page such sentence:

"Racial and anti-Semitic European nationalist parties National Democratic Party of Germany, the British National Party, Greek Golden Dawn, Hungarian Jobbik and Bulgarian Атака are not permitted to join"

About EFD they now have only 4 parties so probably EFD will collapse soon. Even with KNP which is not so keen to join Farage (they have ambitions to form alternative alliance, I don't know how and why but I have heard such rumors). Also I don't see who else Le Pen can be "catched up" to her fraction. Order and Justice as far as I can read from AWPL page (Electoral Action of Poles in Lithuania) don't have bad relations with AWPL, they together form current Lithuanian government so ECR have chance to take from post-EFD another party. Reformed Political Party from Netherlands probably will also join ECR after EFD collapse as they are part of European Christian Political Movement. I don't know how it will be with other, smaller parties but I don't think that EFD will survive neither Le Pen will form fraction.

_________________________________________________________________________________ Christus vincit, Christus regnat, Christus imperat