Does it make sense that there is no image on the Sudarium of  Oviedo while there was an image on the Shroud of Turin? 

Because there would not enough of the bitumen, oil of lavender, alcohol mixture on Christ body to transmit further then the initial shroud that had wrapped his body to pass through to the Sudarium. After his body was wiped down in an attempt to clean then wrap him, he must of kept bleeding.  If that was so, it makes sense that someone would of added another cloth to absorb the blood beyond the Shroud.  There was so little of the print ingredients on Christ body, if the second cloth did not have contact with the body, then it would not be able to receive a print.  

Is it possible that the Sudarium of Oviedo may have an undeveloped image? Yes it could.

If the Sudarium was exposed to the ingredients that made the print possible on the Shroud of Turin, that would mean that the image could still be there but not developed yet.  If the Sudarium was left out in the sunlight or possible UV light, an image of  Christ face may still be able to appear. The only reason it might not, is because the alcohol that would of been trapped in the bitumen could of vaporized by now and thus would not be able to allow the image to appear.

Alternatives.  Yes, there is an alternative method that could possibly reveal an image.  Locating any or all Bitumen of Judea particles existing in the Sudarium could possibly allow for an image to be seen on a computer monitor.  Only if the Bitumen made it to that cloth. To me is unlikely but yet still in the realm of possibility. If the bitumen was carried to the next cloth, its highest concentrate would likely be around the blood stain areas.

The Sudarium also leaves open the possibility that Jesus could of been wrapped with two layers.  Meaning that the Sudarium is possibly a segment of a much larger linen.  If that is so, then there could be more pieces yet not discovered.  That would mean that the first layer of the Shroud would of been wrapped on Christ near or at the cross(Shroud of Turin) as to deliver to Joseph who had a clean linen (The Sudarium of Oviedo) to wrap Jesus before bringing him to the tomb.

Eventually the Shroud travels through Europe to its final destination and The Sudarium travels through North Africa and then Spain to its final destination.  Before the second layer left Jerusalem, it may have been separated and divided so nobody could destroy it.  This would imply a couple of things.  There are missing pieces to the Sudarium, and the cloth to rest Christ head would also be missing.  This is merely a hypothesis.  In order to solve some mysteries, tangible variables must be examined.