Yea Imperial Fleet general chat got real "trade channel" last night. Makes sense though seeing as it could be considered the main hub of travel/capital city.
As to your problem of not finding your group members, could you have been in a different area instance as them?
Not a "dungeon" instance but there are multiple versions of quest areas. ex. Dromund Kaas(1), (2), etc.
To switch to their version you have to right-click on a "greyed out" group members portrait and select the option from the menu that appears.
It can be confusing because general chat crosses all instances. Some instances ratios are unbalanced. Ie. lots of deadly monsters and you (hard to get to your group members) or lots of player and lots of dead deadly monster (easy to reach group members).
Sorry you were pushed to deleting your character and moving servers.