So in 2014 he investigated corruption from 2010-2012. And in the year he started investigating Burisma (2014), Burisma decided to hire the son of the US Vice President. And Hunter himself admits he wouldn't have got these jobs if his last name wasn't Biden. Seems like the time line lines up quite well.
Except you're clueless.
Zlochevsky was deposed from his job as Ecology Minister in Feb or March 2014,following the Revolution. The current PG (not Shokin) accused Zlochevsky of corruption, and abusing his role as Ecology Minsiter to take bribes to provide gas leases to fellow oligarchs...Threatened with Jail, Zlochevsky fled Ukraine and went into exile in Cyprus...
In an attempt to rehab their reputation and demonstrate reforms to the West, Burisma hired HB, a former President of Poland, and an ex-official who worked in Secuurity for the Bush Admin to their BOD. That was the Spring/Summer of 2014...
Shokin didn't conduct any investigations in 2014, because he wasn't appointed PG till Feb 10, 2015. His appointment was not popular with Ukrainians who looked at him as a remnant of the pro-Puitn Yanyukovych Govt (he was PG then as well).
The problem from the start was that the corruption he was supposed to crack down on involved his friends from the old regime. And he was also expected to track down and punish the former Yanukovych pro-Russian militias who had murdered pro-Democracy demonstrators, but again he was part of the govt that the murderers supported.
He didn't do anything to fight corruption or clean up the stench within his own office. And on top of that he didn't make any arrests of the suspected murderers, and those were the two main objects of his job description.
No one liked or trusted him. He was supposed to crack down on corruption from the oligarchs, but the oligarchs were his friends and former comrades.
You mentioned a timeline. The State Dept put together a briefing advising Biden to press Poroshenko to fire Shokin in late Nov 2015. Biden's trip was in Dec 2015...
But prior to any of that on Oct 31, pro-Democracy protestors gathered outside Poroshenko's residence and demanded he fire Shokin... From the Oct 31, 2015 edition of the Kyiv Post...
"AutoMaidan activists accuse Shokin of sabotaging all high-profile investigations, including corruption cases against incumbent and former top officials and the investigation into the murder of over 100 protesters during the EuroMaidan Revolution.
Shokin also faces accusations of derailing his deputy Davit Sakvarelidze’s reform, which envisages hiring new prosecutors in a competitive and transparent process. He has also reportedly failed to declare luxury property, according to recent journalistic investigations.
The problems have gone out of hand so much that more than 100 of Ukraine’s 450 members of parliament have called for Shokin’s dismissal."
About 200 members of the AutoMaidan car protest group on Oct. 31 went to the president’s private mansion… - Oct. 31, 2015. By Johannes Wamberg Andersen
archive.kyivpost.com
And the thing about those 100 parliament members is they were the most pro-Democracy, pro-US members, and they regarded the PGO under Shokin as a bastion of corruption. So any ignorant dolt repeating Trump's claims about Shokin being a good prosecutor, or Biden being the first to call for Shokin's ouster is just dabbling in revisionist nonsense.