The men, from Gambia and Senegal, were crushed while working at Shredmet Ltd in Birmingham on 7 July 2016.
Police and the Health Safety Executive (HSE) are still investigating and inquests have yet to be held.
The families said they were frustrated at the length of time the investigation was taking.
Ousmane Kaba Diabi, 39, who was from Senegal, Alimamo Kinteh Jammeh, 45, Bangally Tunkara Dukureh, 55, Saibo Sumbundu Sillah, 42, and Muhamadou Jagana Jagana, 49, all Spanish citizens, died in the incident.
They had come to the UK to work, some with their families, and were employed along with other Gambians at the plant in Nechells.
Hawa Kaba Dukureh, the 42-year-old wife of Mr Dukureh, said: "Since the incident took place, I've never had any answers from anyone about why my husband died this way.
"I am very sad... I have not stopped thinking about him."
Two men who survived the incident, Basamaba Darama and Tombong Camara Conteh, said they would never forget what they had witnessed.
Mr Darama said he was with the men sweeping up piles of waste metal against the concrete wall when it collapsed.
As he walked away from his friends, he turned to see them suddenly buried under concrete blocks, each weighing 1.5 tonnes, and then scrap metal, which was behind the wall, pouring on top of them.
"I was confused," he said. "I ran and I was confused because I didn't see anyone. The blocks were lying down on them.
"I thought I was going to go crazy. I've never seen this kind of thing before in my life.
"They are my colleagues, we work together, we are friends... and they are dead."
Mr Darama, who still works at the plant, said he was very traumatised by what he saw.
"I'm working there because of my family and I have to. My family has to survive. I don't have a choice.... at night I close my eyes and it's still happening."
Mr Conteh, who suffered a broken leg, said: "I remember lying down and others buried under the rubble. I couldn't move I could just hear noise and from then until now I keep thinking how did it happen and how did I get away?"
Ousman Njie, project manager with the Gambian Association, said: "We think it [the investigations] should have been better than how it is now, but because of legal matters we can't say much but we hope it can be done as quickly as possible.
"We would like it move faster than it is so families know. It's not easy for them to wait and wait."
At the time, Shredmet Ltd, which deals with more than 500,000 tonnes of scrap metal each year, said the wall had been in place for more than two years and had not been subject to any damage that could have caused the collapse.
In a statement, the company said it remained "utterly devastated" by the incident and was continuing to cooperate with the investigation.
It said it was "still in the dark" as to the overall collective causes of the incident.
A HSE spokesperson said it was continuing to support West Midlands Police's investigation. The force said it had passed a file to the Crown Prosecution Service (CPS).
The CPS said it was providing "investigative advice" to West Midlands Police.
The families of five men who died when a 15ft wall collapsed on them at a scrap metal yard say they are still waiting for answers a year on.