That appears to be the case. I can find all of the VTK libs here:
Slicer/.build/VTK-build/lib/libvtk******
I loosely followed these instructions: https://discourse.slicer.org/t/building-slicer-on-a-freshly-installed-ubuntu-18-04/5627
In summary:
sudo apt install qtcreator qtdeclarative5-dev qtmultimedia5-dev qtbase5-private-dev libqt5xmlpatterns5-dev libqt5svg5-dev libqt5webenginewidgets5 qtwebengine5-dev qtscript5-dev qttools5-dev libxt-dev libqt5x11extras5-dev
sudo apt install git cmake
git clone --recursive https://github.com/Slicer/Slicer.git
cd Slicer
mkdir .build
cd .build
cmake -DQt5_DIR=/usr/lib/qt5 -DCMAKE_BUILD_TYPE:STRING=Debug -DSlicer_USE_PYTHONQT_WITH_TCL:BOOL=OFF -DSlicer_USE_SimpleITK:BOOL=OFF -DSlicer_USE_QtTesting:BOOL=OFF -DSlicer_BUILD_DataStore:BOOL=OFF -DSlicer_USE_SYSTEM_QT:BOOL=1 …/
make
I also applied the workaround at the bottom of that thread for fixing the system curl and OpenSSL.
Thank you so much for your time.