The fund of the CTA and the Dalai Lama comes from the sponsors, some sponsors want to use the Dalai Lama's name to boost their credibility and images. The Dalai Lama has millions of followers around the world, his endorsement is a huge value added to many. The Dalai Lama receives money and hospitality when he is invited to give talks and the sponsors get his endorsement.
Many of these sex scandals lamas are very established in the west. They have big centers, they have many rich followers and they are very connected. These are what the CTA and Dalai Lama need in order to get their fund too. If the CTA takes actions on these lamas, their income will reduce and it is of no benefit to them. The CTA is known to be very self-centered, they don't care about others, they just want to make sure they are ok.
The CTA accuses Dorje Shugden of their failure when it is, in fact, their own inefficiency and incapability that causes them to lose their country. From the past until now, the Tibetan leadership has not done much for the development and progress of their country. They are well-known for corruption and nepotism. Until they change, there will be hope for the Tibet cause. Otherwise, it will continue to be a failure.