I’m beginning to get as frustrated as you must be. Can you address the following points?
(1) Can you get a better scan of the schematic(It’s very fuzzy and hard to decipher)
(2) You never addressed all those loose hanging wires, in the first pic, which are not connect to anything. This does not seem right, surely they connect somewhere.
(3) Can you not, when looking at the pics closley, see the glaring difference, between the original wafer regarding, design/profile/contact layout, with the replacement wafer. Not certain why you do not see it!
(4) In the in one pic it shows an orange wire to the right of the two red and white wires, and in another pic the orange wire is missing???
(5) Also in regards to you question about the Meter movement being irratic. This is showing that the continuity is making and breaking. What ever the cause of that needs to be determined. And yes, a short in a tube can be either a solid short or an intermittant one. Is there a Short-Light on this unit??? At least, with the Meter movement flickering, that may be telling us that the Meter itself may be somewhat working, however that does not mean it will be capable of giving accurate readings.
(6) I am also surrprised that no one else, who may be followng this conversation, has offered any input here. There maybe someone aboard here, that has the same Tube Tester, who may know more about this unit, than either you or I. As for me I have a feeling that this Tech of yours may have rendered this unit un-repairable.??? It may be cheaper to find another Tube Tester with the functions you want. Even if you find someone who claims to be able to fix yours (no guarantee there), shipping the unit, to wherever, comes at high cost.\, and hourly labor and parts may not come easily. So unless we can somehow, by some fluke of fate, can find a solution. I don’t know??? But we can continue to work on it. As for me, I think the minimum we need is the correct wafer, and a much clearer Schematic. These units are no more complicated than some of the radios we work on. In some ways it is just a complicated Power Supply Unit, with its multitude of switches, which is designed to apply proper voltages, In order to mimic what is or maybe be considered, normal operating conditions for the said tube/tubes being tested.