The 100.1.0 DB Tools DEB file for Ubuntu 16.04, here:

http://repo.mongodb.org/apt/ubuntu/dists/xenial/mongodb-org/4.4/multiverse/binary-amd64/mongodb-database-tools_100.1.0_amd64.deb

includes a hard dependency on a libcom-err2 package, but the correct package name is libcomerr2 on Ubuntu 16.04

I have attached a brief troubleshooting guide, including steps to tweak the prod DEB file and edit the dependency, which seems to fix the problem for Ubuntu 16.04 at least.

Recommend a brief check to make sure this doesn't affect the other Ubuntu / Deb builds. I did check Ubuntu 20.04 on MDB 4.4, which works just fine, and Ubuntu 16.04 on MDB 4.2 works just fine, but have not checked any others. Only think this affects 4.4 builds released Friday last.

Thanks to john.williams for the initial find!