Wonder if you coulda cleared a tin whisker or something in the old T115 whilst removing and reinstalling it.
Now that you got barberpoling, try reconnecting C202, and go back further and disconnect R242. If still barberpoling, you should be able to zero beat the osc using the reactance coil, though it won't have any sync.
(Digital meters supposedly are high impedance like a VTVM, so shouldn't cause any loading problem.)