Yes. Commits clearly show in progress where both LGPL and MIT code was working together. This clearly show they are a derivative work and MUST follow the original license.
Plus the argument put forth is that they can re-license the project. It's not a new one made from scratch.
Did they eventually remove/replace all the LGPL code?
So, if these commits were private and squashed together before 7.0 was published there would be no violation?