Changing fonts works 100% fine in the default and radiance themes with terminology in Bodhi.
EDIT: Don't worry about it. I just tried the Onix theme with terminology and it resizes fonts just fine. I'll make sure to confirm things myself other folks report.
I'd promise to make a video the next time I report an error but it would just be declared another fluke on my system. In fact after going back to the default theme and changing the font I can now return to Onix and still change the font. That does not mean the previous glitch didn't exist..only that it's not consistent and may involve other things.