I did some minor modifications to the sources and managed to again compile such an ancient piece of code on my Ubuntu 16.04 64bit.
Changed the "build" to build4 and published it as a release on the github fork:
https://github.com/brozkeff/Slothcoin/releases/download/v1.3.1-build4/slothcoin-v1.3.1-build4+ubuntu16.04-amd64.zip
It is dynamically linked to libboost 1.58 libraries, Berkeley DB 4.8 and OpenSSL 1.0.2 and it expects these libraries in the appropriate folders. By exporting LD_LIBRARY_PATH with the correct libraries I managed to finally run this binary made on Ubuntu on my Debian server recently upgraded from Debian8 to Debian10 but clearly it would be nice to either have the libraries statically linked and have a more generic binary without dependence hell, make some snap or AppImage package, or build it independently for each distro.