As far as I remember, there was a feature in CS:GO to backup rounds, however I can't find how to enable it. Also, when I checked my csgo folder, I saw some old round backups. Here is a picture of the last one (Notice the timestamp? It was my last day with my old pc. Also my last match was 10 mins ago):
Edit:
I also found the command mp_backup_round_file
, but it is enabled.
More info:
"mp_backup_round_file" = "backup"
"mp_backup_round_file_last" = ""
"mp_backup_round_file_pattern" = "%prefix%_round%round%.txt"