Worst case, I indeed just add the Issue event as a kind to fetch for in the Tasks section.
But to me, this is again the same debate as the one about Replies. Where the conclusion is that is using one kind (1111) for replies, on anything, is the most elegant. And you just fetch or the Replies that tag the event (or type of event) that you want to see the Replies for.
We don't use different kinds for Zaps on Articles, Zaps on Threads, Zaps on Repos, etc...
We don't do it for Replies, nor for Labels, nor for Reactions, ...
If it's the same exact event structure, with the same purpose → I'm using the same kind.