Yes, this is correct. For accessing Dev Basic training a licensed dev env is required.
UiPath and ProcessGold are going to merge their Academies by end of Q1 next year. From there, UiPath is going to provide a free dev env to developers.
Until then, the option to provide a ProcessGold developer environment for the training of the ProcessGold platform is not possible, since the ProcessGold platform is designed to be used within a single organization where developers collaborate on creating applications.
I do not have more information at the time being, but I hope the above helps.
Have a nice day.