rushing places not listed at zones?

There are some places like Pi Lambda Phi which is not listed on for a zone day, but is a part of the University's recent recruitment guide. They are just allowed back this year according to the scorecard. Are these places good to rush?

There are also other houses like Delta Sigma Phi who are supposed to be coming back but aren't listed anywhere.

Basically, TLDR, what's going on with a lot of houses coming back and should they be rushed?