I apologize for not making the resistance measurements in a more expedient manner. Weather and family issues are, or were, weighing on me heavily.
I will look at my RCA service literature again for this receiver to see if I can offer any useful guidance. It is doubtful, in my opinion, that there exists a shorted winding on the horizontal output transformer. In my experience, even one shorted turn results in catastrophic effects; nonlinearity, foldover, or complete failure of the transformer after a few minutes of operation. A “ring-down” test is simple to execute and provides a pretty comprehensive assessment of the transformers health. Certainly you are familiar with this, but for readers who may not be:
http://www.repairfaq.org/sam/flytest.htm
While a transformer failure isn’t out of the question, those employed in the CTC-2B chassis were far more durable than say ones in later models like the 16’s or 17’s.
The drive waveform asymmetry would be a place I’d start investigating.
Regards.