The maintainers
Generally operate to charge within a narrow voltage range and thus a fully discharged battery is below the voltage at which the maintainer will kick in.
Jump start the car and go for a 45 minute drive with accessories off. Then bring it back and put the battery on a maintainer for 24 hours. Then remove from the maintainer for 24 hours and place a load tester on the battery at as close to 70 degrees as you can get. The result will tell if your battery is good.
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