Well, Heidi Shannon wasn't replaced with Matt Mercer, and we haven't heard anything about the circumstances as to why she isn't in. If Larian hadn't made a huge song and dance about replacing him with Matt Mercer then I'm sure she's get more questions about her, but that wasn't the case. We haven't heard anything to indicate she wanted to play the part but Larian was ignoring her, but unfortunately for JC fans, there is some indication that he was never in the race to begin with, despite being a big name voice actor in his own right and being interested in the part. So you have what looks like disrespect for the original actor to leverage fanservice for an entirely different setting. I can see how that's not a good look in some fans eyes.