i might get some cotton clothes line.. and tie them all together a couple feet from the ground ...

cotton so it will rot off.. if you forget to remove it ...

it may be too late on some of thehorizontals... maybe they should just be removed ... hard to tell when im not standing in front of it ...

in hindsight.. you might have been better off.. if you had provided some structural guidance as they started growing ....

lastly ... these can be huge unruly plants ... you might be fighting a losing battle.. trying to tame it... in a small yard ... it will eventually go skyward .. all by itself... but it might be 6 or 8 feet wide... including swallowing the fence ... by the time it does it itself ...

ken

scroll down to see mature plants https://duckduckgo.com/?q=Elderberry+plant&t=ffcm&iar=images&iax=images&ia=images

Wait for it to recover a more natural shape on its own, this is only the very beginning of its response to being whacked down.

Rampant sucker-growth that's so long & slender it's inevitable that it will lay down -- some die-back shrubs of mine do that. One thing that would've helped is to trim back the suckers earlier (maybe several times over the growing season) so they would branch out some.