So I was testing out the bug fix for the dice rolling and tried to load a character in my testbed that had previously been imported/linked from Demiplane. It would not load. I closed my demiplane and roll20 windows, cleared the browser cache and cookies, and then restarted chrome. Still had the same problem. I then imported a new character to see if it would work and it did. Then the old characters started to load as well.
This post serves two purposes… one, a bug report… two, anyone else who has the same issue, just import a different character and the old character should load.