I could be wrong here, but I think そこに here is being used as a way to add an additional comment. I know that そこに can be used somewhat like “additionally, moreover”, and in this case I could see it being something like “~~… and (moreover - to comment further on your ability to do what we can’t) it’s exciting/shocking” or something like that.
Or something else I was thinking, since そこ also means そのこと (source: デジタル大辞泉), I could see it just being translated as “in that (you can do what we can’t easily) I’m shocked” but I’m not too sure. I’m just kind of brainstorming ideas here. I personally would think it’d be the former (moreover/to comment further) meaning.