There is an easy solution to this "he said, he said" Turn the transcript of the phone calls to Congress and remove all doubt.
Most importantly, turn the IGs report on the credible whistle blower over to the intelligence committees in Congress, as per the LAW....
The IG said it was urgent, and security risk, congress must get it.
This is a Trump appointed IG of the intelligence agencies, the agencies that Trump has tried to make his followers believe is corrupt. That IG was picked to come down on the Intel agencies...
And that IG, after investigating the whistle blower' s concerns of corruption and security risks, SAID the whistle blower concerns were VALID and LEGITIMATE, it was URGENT that congress get it. The law states congress SHALL get the report within 7 days.
Trump admin is breaking the LAW.