Nunes is the man. Period.
He can now subpoena the whistleblower, which will create a massive poopstorm in DC as the whistleblower is someone with full knowledge of this saga and someone who was briefed by the future Ukrainian defense minister - aka the LTC.
They can subpoena Nuland and ask her about the state department partnerships with Soros in Ukraine and how she influenced their investigations and who ordered her to do so.
I also believe they can bring in Ukrainian witnesses to whom the state department refuses to grant a visa.
They will fight this tooth and nail, but if it happens expect them to make room next to the Custer memorial for the Schiff memorial. Both of them suffered the same disease of arrogance.
Nunes, Meadows, Ratcliffe, Stefanik, Gaetz, Biggs, and some others, all doing yeoman’s work.