Per CAP (not sure if you are accred by them) second type is only required for computer crossmatch and since the computer is down, there should be no computer crossmatches going on. Other than that, 1 type on file is perfectly acceptable to issue any type blood. However, many labs use the second type to check for WBIT. Anyway, you need to follow your lab policy. I personally, would feel uncomfortable giving non group O type specific with just one type on file during massive computer downtime.