On an old Bally I would have thought it more likely to be a faulty coil, or if you are lucky a break in the wire near the lugs. The hold coil is the fine wire. Faulty EOS on a Bally means the coil will not fire (EOS no contact at rest, broken wire leading to EOS) or will blow the fuse (EOS never opens when flipper activates).
cheers
Ian
Looks like Ian wins the prize here
Rich - Thanks for the follow-up post confirming the repair. This will be a great reference for the future.