I had a search through your characters and couldn't find any sign of the guild sadly. Can you remember which characters were the leaders of each guild?
I just had the exact same thing happen in the merge from Bergeren Colony to Satele Shan., I had an Imperial guild named Shadow Consortium under the control of Moerte and a Republic Guild under the control of Quedaingo. I used to be a subscriber and purchased all the perks when I went to f2p so that my characters could access both guild banks. However, now that I've logged back in after a few months away because of school, both my guilds are gone along with their mostly full guild banks. I'm not even sure what happened to my other guild members, I don't see any sign of them anywhere.
EA QV TeamIf your Guild Leader character did not log on for more than 4 weeks, the system would have assigned leadership to the highest ranking active member of the guild. See here for more info: https://help.ea.com/en-us/help/star-wars/star-wars-the-old-republic/swtor-guild-management/
