I just learned this run and I'm currently running on version 2.3.5

I'm not gonna need to downpatch am i?

I don't think you should have to, in all the updates since 2.2.3 there have only been hotfixes/patches with the streamer integration stuff so shouldn't make a difference to the run.

There wasn't anything in the run on 2.2.0 that I wasn't able to do in 2.3.5

There's been some small new discoveries I've made in my runs, i'm not sure if they'd be doable in 2.2.0 since I haven't ran that version. But I'd bet they can be

Developer here! 👋

Just as Fox said, there are no major changes between those version; all versions 2.2.3+ are the same in terms of gameplay/story/mechanics wise :)