It’s possible, but highly improbable.
TweetReports is not an archive service. We do not access nor store every tweet from Twitter.
Only keywords (including hashtags) that have been saved as a Tracked Search are actively monitored. Therefore, in order to get a complete transcript of a Twitter Chat, the hashtag must be saved as a Tracked Search before the chat occurs.
That said, because TweetReports pulls and temporarily stores tweets from users searches (which may include your hashtag), it may be possible to search and get tweets for a hashtag after a chat has taken place. At best, you may only get a partial transcript.