How to obtain an access token for the Adobe Creative Cloud edition?

I still guess what is the Adode standard solution here.

Look, a company use Creative Cloud, including Adobe Sign.

They do not want to convert their subscription. Actually they would like a very simple thing:

send Adobe Sign reminders from another program. I am a developer and I know how make it.

It is simple using the Adobe API. But.... there is no possibility to generate token because I cannot get API key for this account!
But, a strange thing - they have an API token in their interface they use for another program (have a look at the picture).

It means they can use API for connection. But how? how I can get a token like on the picture (not having API applications options in menu)?