Looks like they're using the NMO as a complexing agent for the aluminum species, not as a solvent (mp = 180°C). However, I am a little surprised it doesn't just oxidize the DIBAL, but there's apparently precedent for this sort of thing.
Anyway, sounds like your initiation isn't working. Look at all your reagents and solvents. Is your THF dry? Have your NMO, DIBAL, or propiolate decomposed or become contaminated? Are you rigorously excluding water and oxygen? If those are all good, you could try trapping with an electrophile from the paper. If that works but your substrate doesn't, than this pathway might not be one you can use.