bells & whistles wrote:
They did not release the full transcript.
Ditto this. It would be surprising if there was a full transcript of the conversation. Since Nixon, Presidents have been loath to tape their conversations, so any transcript would be based on notes. When a President talks to a foreign leader, the translator and others take notes. These are collected and compiled into a "Memorandum of Conversation" summarizing the conversation.
There are two things the second whistleblower could add: 1) Direct Knowledge: The first whistleblower did not have direct knowledge of the call; he was worried based on what other people told him about the call. The second whistleblower has more direct knowledge. This will make it harder to attack him as giving "hearsay" evidence. 2) New Information: It appears the second whistleblower may have new information about the call.