Tim,
I have never heard of a Bottlehead transformer being bad out of the box. As a matter of fact, you have to molest them pretty well to damage them. The fuse should always protect the transformer.
So, I mean don't worry about the transformer on those readings. Check from transformer T4 to transformer T5 and see if you get ~6.3V AC.
If not there is something dragging it down. Check the orientation of the capacitor and the diodes. They can be a booger to get right. I've been doing this a long time and I get one backward every so often still.
Let me get this right, the only voltages that are off are the ones listed? Right? If so you are reading wrong. If the downstream voltages, say T1, are good then it is just a problem reading the early terminals.
Terminal 21 is connected to the cathode. If it is low as reported then the associated plate, terminal 22 should be way high because it isn't conducting. Try rewetting the solder joints at terminals 21 and 22 as well as tube pins B6 and B8.
Looking at the other readings, something is off in the power circuit.