That's interesting. I download packages NOT from my repository all the time, sometimes they work, sometimes they don't. In over 10 years it's never amounted to more than just removing the package and dependencies after you realize it's a no go. Besides, just because the dependencies aren't in your repo doesn't mean you can't get them. If you're using the most popular hacking distro in the world and you can't figure out how to install software outside of your repo without breaking it, then maybe cyber security isn't your thing. If it's compatible with Debian, you can get it to go. Before anyone comes out guns a blazin, I'm not saying your wrong, I'm just saying it's possible. I obviously wouldn't advise it unless you have a thorough understanding of the ins and outs of your distro, but that's what open source is all about. Tweaking it and changing it to fit your needs. I say try it, if it breaks, reload it and try again. Or just play it safe and quit.