Yes, many. Among them are the UN Charter, the 1975 Helsinki act, the 1990 Charter of Paris, and the 1997 NATO-Russia founding act. None of which place any limit on NATO's expansion or which exclude Ukraine from joining NATO. All of them recognize each nation's sovereign right to determine their own alliances and allegiances. Russia is a party and signatory to every one of these treaties and agreements.
Make note, Bashi didn't provide any treaty or agreement that limited NATO's expansion - no such document exists. He provided you a video of a guy saying that Putin (Putin, specifically) warned us not to. That's different.
There is no reading of the facts which alleviates Russia's full responsibility as the aggressor in this conflict. They are in direct violation of every one of those treaties. One could argue, as Bashi does, that it was unwise to allow NATO to expand eastward, and that can be a basis for a good argument, but it's also fully opinion, and there is no treaty or arrangement that Ukraine or any other NATO member state has violated that Bashi can point to which places any legal blame on the West. Ask him to provide a receipt. He'll be unable.
In 1999, Lithuania, Estonia, and Latvia (all former Soviet satellites) joined NATO. Czech and Poland also join the same year. In particular, Poland's accession into NATO had been underway for the entire decade - starting in 1990. Notably, Russia signed the NATO-Russia founding act in 1997 - which as far as years are concerned, comes after 1990 the last time I checked. Also of note, Poland was once a former Soviet satellite. Hey, the more you know! Right? Tough for me to know how long and on what setting I would have to microwave my brain in order to believe that Russia was super upset about its former satellites joining NATO, but would also simultaneously sign an agreement saying it's cool, but then again, I'm no statesman. Hence, why the entire line about them being upset over Ukraine joining NATO is total horse shit.
In 2008, Ukraine (and Georgia) were "invited" to NATO at something called the Bucharest summit. As his final act as President before stepping down, Putin expressed discontent that Ukraine would be invited to NATO. Understandable. Falls squarely into Bashi's opinion that "we provoked" this conflict. We get it. Putin didn't want Ukraine in NATO. And because Putin didn't want it, it's our fault. This is the one fact Bashi can lean on and which comprises the totality of his argument. Putin didn't want it. Undisputed.
Flash forward to 2014 and Vlad is back in power pushing little green men into Ukraine. I, for one, can always tell who the good guys are in any conflict by who's soldiers are wearing unmarked uniforms, occupying another state's parliament buildings, and then holding "elections" for them which in turn result in the dissolution of their government.
Flash forward to 2022, and Putin has his full-on invasion. Personally, my opinion is that Putin is concerned about Ukraine becoming (more) Westernized because of the enormous economic power they wield both in terms of agriculture and energy. Putin (or Russia) losing a substantial amount of their economic leverage over Europe would be strategically devastating for Russia. NATO expansion is a pretext because Ukraine can continue down the path of Westernization with or without being a NATO member state.
Yeah, there is a complicated relationship between NATO and Russia given the legacy of warfare in Europe in the 20th century, but there is nothing which has ever limited any state from choosing their own alliances - and this includes Ukraine. Anyone who wants to read them can find them on the internet. Russia has signed all of them.
I predict two things. First, that this war will end with Russia annexing eastern Ukraine (Crimea), permanently. As the trade to achieve peace, what is on the west side of the front (Ukraine) will eventually be allowed to join NATO. The second prediction I have is that Bashi will down vote this comment.