I have the same problem, as additional information, running directly OpenROAD GUI and opening the ODB file generated by OpenLane shows the following error:

~/Desktop/OpenROAD-flow-scripts$ openroad -gui
OpenROAD v2.0-12143-g4aabf0d3c 
This program is licensed under the BSD-3 license. See the LICENSE file for details.
Components of this program may be licensed under more restrictive licenses which must be honored.
Signal 11 received
Stack trace:
Signal 11 received
Stack trace:
 0# 0x0000558283392C48 in openroad
 1# 0x00007EFD877EE090 in /lib/x86_64-linux-gnu/libc.so.6
 2# gui::RenderThread::drawBlock(QPainter*, odb::dbBlock*, odb::Rect const&, int) in openroad
 3# gui::RenderThread::draw(QImage&, QRect const&, std::set<gui::Selected, std::less<gui::Selected>, std::allocator<gui::Selected> > const&, std::array<std::set<gui::Selected, std::less<gui::Selected>, std::allocator<gui::Selected> >, 8ul> const&, std::vector<std::unique_ptr<gui::Ruler, std::default_delete<gui::Ruler> >, std::allocator<std::unique_ptr<gui::Ruler, std::default_delete<gui::Ruler> > > > const&, double, QColor const&) in openroad
 4# gui::RenderThread::run() in openroad
 5# 0x00007EFD883959D2 in /lib/x86_64-linux-gnu/libQt5Core.so.5
 6# 0x00007EFD8B6C5609 in /lib/x86_64-linux-gnu/libpthread.so.0
 7# clone in /lib/x86_64-linux-gnu/libc.so.6
Segmentation fault (core dumped)

On the other hand by manually adding the lef and def file the system loads correctly, so I think the problem may be in the ODB file.