[old_tv_nut]

I don't see any waveforms on the page I linked, and I don't have a schematic, so I would just be guessing at this point.

Do you have the chroma oscillator adjustment instructions for the 9-27 module, and do they work?

In any case, it seems like the problem is with the 9-27 module or its connections. It's suspicious that both replacements seem bad.

Not sure what A.C.C stands for here. Automatic Color Control? If so, should not affect oscillator lock, which should be a function of the A.P.C. (Automatic Phase Control of the oscillator).