From what you describe the lane seems to be grippy and not overly oily - when the Punisher works from the start.
From this desdcription and the fact that the Nemesis does not work (probably burning up, lack of head oil), I do not think that you need something strong as an Ambush - it would probably end up quite the same.
How's the Punisher drilled? If it is drilled for length/snap or stacked leverage, a possible solution could be another one with a rollier/earlier drilling, pin under ring for a high tracker (drilling pattern 2E or 3E from Brunswick). A Power Groove pearl reactive or a Power Groove Dry/R would be an option, too, since they are weaker than the Punisher and have a higher RG, thus saving energy for the backend.
A perfect ball for your situation (although out of production for 2 years now) would be the Popwer Groove Proactive Plum Pearl, a polished light load particle ball with a high RG and a milder coverstock than the Ambush. I am not sure if a polished-up Black Sparkle Power Groove would do the same, the Black one might be a touch stronger. These balls are/were smooth on medium-dry conditions, and the particle would help on carrydown and avoid skid/snap spasms.
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DizzyFugu --- Reporting from Germany
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