It works now. It definitely didn't before when using Sync for Lemmy. That kind of mistake wouldn't have worked on the reddit website either. I had seen it a million times. Not sure if the Lemmy web site would handle it right.
Both versions work on my end.
I'm surprised to hear that.
Markdown libraries normally see the closing parenthesis in the URL as the end of the link markdown syntax of [text](link). You had [text](link(stuff)) which is parsed as [text](link(stuff) A smarter markdown parser could handle it, so whatever app you were using might do that.