Abusive ex and protecting my kids.

My ex husband and I have been separated for over 3 years now. During out 20 yr marriage he was extremely abusive both mentally and physically to myself and my 2 older children (my kids are now 10, 13, 18 and 20).
At the beginning of the separation things were amicable and the 2 younger girls visited him for 1 night a fortnight. He barely saw or spoke to the older 2 and when he did it was false promises of seeing them and in many instances he would talk to one when he picked the girls up and ignore the other, even on b.days etc.
When he has a girlfriend his kids are almost forgotten about, he is "too busy" or "too broke" on his night he is meant to have them so they are being let down constantly and I am left to mend their little hearts.
His latest girlfriend has an issue with my 13 yr old so now her Dad has told her that he can't see her anymore but still wants to see the youngest. He found out about 18mths ago our oldest is transgender and I have seen communication between him and his gf on social media making fun of her and refusing to accept her. The siblings are disgusted by theit sister not being accepted.
I have NEVER refused the kids go see him, I feel it is of utmost importance that the girls have their Dad in their life but the older 3 have given up trying to make a relationship with him. Even though I know he drinks to excess and has been a horrible violent drunk in the past, the youngest has been lucky enough to have not seen it ot been affected by it like her siblings.
About 10 mths (the last time the 13 yr old went to visit) ago it came to my attention he has not had a bed for them the whole time they have been visiting, the 10 yr old sleeps in his bed and the 13yr old on a swag. I was upset and asked him to put the bed the together (we went halves in all furniture when we split) and up until this day he still has not done that. So I have been in contact with a lawyer, child support and DCP to begin to get half of financial assetts etc and get child support taken out rather than go private.
Just before Christmas I informed him until things change, the girls get a bed, space of their own so it is "their house" too and he stops drinking around them, they will no longer be going to his house. He has not tried yo make contact since but my youngest has begged him to visit her and spend time with her not at his place. He did this once for 5 hrs but does not seem interested and always has excuses.
My question is, I know this is hurting my youngest as she adores him so much but I am doing this to protect her. Am I doing the right thing?