I agree the timing is bad, but what were his true intentions? Why would he make anything known on it 1 1/2 years before an election not knowing even if Biden would win the Dem. bid? IMO he had Giuliani in Ukraine in late 2018 looking for DNC collusion in the 2016 election after he was exonerated of wrong doing in the Mueller report. Mueller report was not complete it never mentioned anything on Hillary or DNC involvement, the Steele dossier, Pressure put on Poreshenko to help her by making him think Trump would not help him with Russia. All of which came out from the congress investigations, and IG report, there is a criminal investigation into this now too.
I think they tripped over evidence in that investigation over Biden's influence which lead to could you look into the rumour of then VP Biden put pressure on your then Pres. To fire the prosecutor looking into Burisma's corruption investigation that has the VP Biden's son on the board, it doesn't look good.
That's where doubt enters into this for me, what his true intentions were. I think it was expected by political strategists in 2018 that Biden would run in the next election, it was likely in the air at the very least as he looked to be the best the Dems had to offer, which really is shortsighted on the Dems. Giulaini could have been there at that time looking for what you mention, yes, that is possible. But again Giulaini because of the contacts he ran with and with info (more to come?) backed up with recordings coming out from camp Parnas this whole picture is yet to be painted.
It will be more telling when all investigative findings (that can be) are made available to the public and so the questions we all ask may be answered.
Tripped over evidence? Okay. But the problem there is that Shokin was actually removed because he
wasn't doing enough to investigate corruption, including that of Burisma. So why would Biden want him removed for "investigating Burisma" when in fact he wasn't. I have a hard time with that.
I'm curious if you have read the Mueller report? I only ask because I have a copy and have peeked at it but have not read it as of yet.