The state of DirectAdmin.

LoL... if that is the case, maybe those are companies with little knowledge. Because everyone ruing a bit of a decent hosting company knows DA is still alive and kicking and even if they don't know, they should at the very least have a look for themselves. How difficult can it be to try directadmin.com or to use Google?
So company's thinking DA is out of business... well personally I think they are plain stupid, sorry.

If company's try to push their customers into another hosting panel, that's a business decision and has nothing to do with not being alive.
DA is much easier to upgrade and uses less resources then Cpanel does. I can't even get newer version of cpanel for more then 6 months for a customer because he's still ruing Centos 5. DA has support until March 2018 for Centos 5. DA is cheaper then Cpanel if you buy lifetime, which is not possible for Cpanel anymore.
Cpanel has maybe some more options. But I rather do a ./buil update to update my php then a complete run of easyapache to only update php from 5.5.29 to 5.5.30 or something like that, so the minor upgrades.

1.) Would be a good idea, maybe Facebook is also a good idea. There is some kind of a page, but not supported or owned yet. Cpanel has one.
2.) Companies have to allow to have their name mentioned. It's can be also some work to keep this up to date.

There is an advertising section for this at the bottom end of the forums. But these are mainly support forums. Company's can also use webhostingtalk forums for hosting offers.