This keys relatively happily to L.dentata if we assume that it is not Lobelia simplicicaulis. However, the foliage is not as coarsely toothed as I would expect and the inflorescence is pretty sparse for L.dentata. I appreciate that we cannot make an exact determination either way without ripe seed but I would go for Lobelia simplicicaulis which prefers a taller, wetter grade of forest so is more common in these montane settings.
@Tapirlord I missed your comment until just now, planning an excursion for tomorrow and checking out sightings. Saw your sighting, and I agree. I had not considered simplicicalus but it is a better fit.