Comment 5 for bug 1766555

>Did you mean it was removed because it fails to build on mips/mipsel?

I know where to find the package history, but I don't know more about the specific details for this package. :) Now that you mention it, that seems a bit strange since Ubuntu doesn't support mips(el). Looks like the package had failed to build on arm64 and was missing dependencies to attempt a build on armhf (https://launchpad.net/ubuntu/+source/openscad/2015.03-2+dfsg-2ubuntu5). Could possibly also be that it failed to build when attempting to rebuild packages in the archive but I don't know.

>Can I do something to help getting this package back into ubuntu?

One way would probably be to get the package resynced from Debian to Ubuntu. Note that currently it is marked as affected by two release critical bugs (the mips build failure and another) https://tracker.debian.org/pkg/openscad, so it might be easier to reintroduce the package if those were fixed. Also note that at the time 2015.03-2+dfsg-2ubuntu5 was removed it contained some Ubuntu-specific patches (one can tell by "ubuntu" in the version number), and perhaps these would still need to be included to build and run as expected in Ubuntu.