No, I think the problem can be worked around. I think there might be a couple issues here.
The first is that the project in question is not set as a back translation project. To have this work correctly in Paratext 8.0, I think it would be best if the project was first changed to be a back translation of the correct base project in Paratext 7.x. This can be done by changing the setting at Project > Project Properties and Settings > General tab > Type of project.
However, I don’t think that problem is causing the exception.
I was able to migrate your project just fine, so I think the exception is caused by a bad value in the C:\My Paratext 8 Projects\languageNameToCode.xml file. Could you try deleting this file to see if that fixes the migration problem?