expression
but I don't know; or something like that; I guess
Colloquial phrase originally from Kansai dialect, used at the end of a statement to soften it, express uncertainty, or distance the speaker from the claim. Similar to adding '...or something' or '...I guess' in English.
明日は晴れるらしいで、知らんけど。
I heard it's going to be sunny tomorrow, but I don't really know.
あの店、もう閉まったんちゃう?知らんけど。
That shop might have already closed, or something like that.