I'm not defending anyone. I did not create a bubbeh maaseh and I am not saying that Chaim Walder isn't guilty. I'm just telling you what the chofetz chaim wrote. You can and should take all the steps of protecting victims and potential victims necessary but until the matter is proven, the halacha is that you cannot completely believe that the allegations are true. You are allowed to suspect but you cannot accept as fact.
Part One, The Prohibition Against Lashon Hara, Principle 7, Seif 4
1
וְהוּא הַדִּין, אִם יָצָא (ח) קוֹל עַל אֶחָֹד, שֶׁעָשָׂה מַעֲשֶׂה אוֹ שֶׁדִּבֵּר דָּבָר, שֶׁלֹּא כָּרָאוּי עַל פִּי הַתּוֹרָה, בֵּין שֶׁהוּא אִסוּר חָמוּר וּבֵין שֶׁהוּא אִסוּר קַל, אֲפִלּוּ הָכֵי אָסוּר לְקַבְּלוֹ לְהַאֲמִינוֹ בְּהַחְלָטָה, רַק לָחוּשׁ, עַד שֶׁיִּתְבָּרֵר הַדָּבָר, וְעַל אַחַת כַּמָּה וְכַמָּה שֶׁיִּזָּהֵר מְאֹד, אִם רוֹצֶה לְסַפֵּר אֶת הַדָּבָר לַאֲחֵרִים, (ט) שֶׁלֹּא יְכַוֵּן לְהַעֲבִיר הַקּוֹל וּלְגַלּוֹתוֹ יוֹתֵר, וּכְמוֹ שֶׁבֵּאַרְנוּ לְעֵיל בִּכְלָל ב' סָעִיף ג', עַיֵּן שָׁם הֵיטֵב.
The same is true if a rumor has spread about someone that he has done something or said something not in accordance with the Torah, whether a greater or lesser issur, it is forbidden to accept it, to believe it implicitly, but only to suspect, until the thing is clarified. How much more so must he take care, if he wishes to tell the thing to others, that he have no intent to spread the rumor and to reveal it further, as we explained above (viz. Principle II, section 2).