Then you need to look a little closer to the log line you are trying to match. For instance, before the last GU(in English), all chat socials did not have a space after the comma and before the opening quotation mark. Your original regex stated that you wanted to match lines that either had a space after the comma, or did not have a space after the comma. We now changed it so that the space is required to match, but do the log lines look that way in German? If not, you will wish to remove the space from the Regex.
BTW, I have a simple javascript regex tester here:
Regular Expression Tester