Level 59 and need Co-op for first time

I’m at Level 59 in UVHM and I’m having trouble getting past Wilhelm. Well actually it’s not Wilhelm but all the Loaders at the end of the gully where you re-spawn. Whilst I am (unsuccessfully) trying to get past these Wilhelm is on the other side of the arena charging his shields. All my launcher ammo goes pretty quick. I have made it to this level as a solo player and now think I may need some help in Co-op.

Is it possible to arrange co-op events or do I just go on the public network and hope somebody joins in? Sorry to ask such a basic question but this will be my first time playing on a network.

There are a few requests for co-op play on the Forum but these are over a year old.