Issue won't win voters away from DAP, probably make it stronger.

But this isn't the intention of the expose.
The expose's intent and beneficiary is in this order.
1. Anti-Lim faction in DAP gets rid of Lim Guan Eng (go to jail) and gets even more DAP votes (sympathy due to LGE).

2. BN faction gets to put away an eyesore and gives Lim Kit Siang a smackdown, also exposing his hypocrisy.
Either way, 2 sides will benefit from LGE's political demise, the other DAP faction and BN, so the odds are really against LGE this time, even the evidence points to him being guilty.

He will go to jail for a long long time.
In a way this is good for DAP in the long term. It removes a stumbling block in their party, mainly the old guards, and allow fresh new blood in. This allows more dissent and democracy within the party itself.