|well considering it was an airlock that had been damaged and was proably not in use, so a good deal of the equipmement might have been move to the air locks that where still in worrking order leaving only minimal emergency gear there.|
Possibly it would be too many pressure suits to put to make this warship "safe", I think that it was real bad luck that all redundancy system failed and normally they wouldn't need such pressure suits, it would be mainly a waste. They had masks but we have seen that those are used when fires and battle damages have polluted the atmosphere. This is maybe the most likely danger rather than airlocks fail.
It also looked like a cargo airlock (pretty much the dimensions of a viper launch tunnel) so possibly not even a system usually used for people to go outside.
Your point may be valid, too.