You would be better served to just stick to what was actually said. This was a "prior working relationship" with a prominent Democratic Party politician. It doesn't say anything about still "working", as in present tense. It's also very telling that the "whistleblower" volunteered this information. The Inspector General, Michael Atkinson, didn't have to dig for it. It sounds like this person is prepared to be accused of a bias, and is prepared to handle that accusation.
Also, as more and more of the "whistleblower's" claims are verified, this person's motive for lodging the complaint becomes less and less significant. Using a perceived bias to damage the credibility of a "whistleblower" will only work when the substance of what that person alleged, has not yet been proven. There comes a point when a person's credibility is no longer relevant, if what they are saying can be proven either true or false.
Once again, we already have the transcript of the July 25th phone call between Trump and Zelensky and combined with the Trump Administration's own admissions, it can be concluded that the following 3 allegations at the core of the "whistleblower's" complaint, have been proven true:
1) Donald Trump did request that the Ukrainian President Zelensky assist his personal attorney (not the Department of Justice), Rudy Giuliani, in an investigation of the Bidens during their July 25th phone call. The "whistleblower" must have had a source who was privy to the call. That wasn't a lucky guess.
2) Trump had placed a hold on hundreds of millions of dollars in military aid from the United States to the Ukraine, just a few days prior to the July 25th phone call with Zelensky. This was done even though these funds had already been approved by Congress. Trump's explanation for this hold has changed. At first, Trump claimed it was because he wanted European countries to share in the burden, but that wasn't credible because no other country even knew that the hold had been placed. So then, Trump changed his reason to concerns over Ukrainian corruption, which doesn't make any sense either, because members of the Trump Administration have done business with the Ukraine. The fact is, that to this day, no explanation as to why that military aid was placed on hold has been given, which makes any sense.
3) Finally, the "whistleblower" alleged in the complaint filed, that "The transcript of (the call) was loaded into a separate electronic system that is otherwise used to store and handle classified information of an especially sensitive nature." even though, there was no other classified "factual" material in the transcript that would justify a move to a more secure server.
These 3 core allegations made by the "whistleblower" have been either proven true by the July 25th transcript of the phone call between Trump and Zelensky, or through the Trump Administration's own admissions. These allegations weren't the result of conjecture. The "whistleblower" obviously had solid sources either close to the Trump Administration who were privy to the July 25th phone call or perhaps even within the Trump Administration itself. Trump is simply lying when he claims that the whistleblower complaint is fiction. The fact is, the whistleblower got almost everything right... and the core of the complaint is spot on.
Does motive or bias really matter? If what the person said has already been proven true? No.
