you can, but you don't need
to. You can do it yourself.
Looks like the YT channel is not connected to Google+ at all currently, correct?
In that case the process would be:
▶ Connect the channel to Google+ as a person
▶ Invite that person
to be a manager of the Page
▶ Accept the invite (easiest way to do that is to view the page as the YT / Google account "person" and accept via the dialogue that is shown to "people" who have been invited).
▶ Go to http://www.youtube.com/account
or > advanced (it was a while ago I did this), and disconnect the channel from the account profile
and attach it to the page
that the "person" now manages
. (YouTube can now list the page as an option because the account is a manager of the page).
▶ Once the YT channel is correctly attached to the page the " Videos
" tab for the page: https://plus.google.com/+DejanSEO/posts
will read as " YouTube
Post clean up is to remove
the "temporary person" account and (if there is no more data that you need in that Google account
) I would delete the account entirely. That step gives people the willies, but it is no longer needed. YouTube management is now done by all
"managers" of the page.
Any of those people can "switch identities" on YouTube and manage the channel.