How safe is LTC Alexander Vindman from reprisal?

Very, especially if the Army is saying things like this:

“Lt. Col. [Alexander S.] Vindman, who has served this country honorably for 20-plus years, is fully supported by the Army like every soldier, having earned a Purple Heart after being wounded in Iraq in 2004,” Army spokesman Matt Leonard told Military Times on Thursday. “As his career assignments reflect, Lt. Col. Vindman has a long history of selfless service to his country, including combat. Lt. Col. Vindman is afforded all protections anyone would be provided in his circumstances.”

Suggestions that this officer might suffer career damage for testifying in connection with the current House of Representatives investigation into President Donald J. Trump's attempted political quid pro quo with Ukraine are farfetched. As between the two, who is more likely to be in federal service on January 21, 2020? Odds on whether LTC Vindman makes Colonel?