Can too thick render cause mould?

Has anyone had ,and treated ,extensive mould in a house?
We have a house we rent which we bought last year and had damp. We had the damp proofers in and the injected a new dpc and the we had it re plastered. However, now after this winter there is mould growth on walls, including upstairs where there was originally no damp.

Obviously this is a health hazard and we have a family of 6 in there.

An agent I spoke to said they were having similar problems with a house a few doors down and were told the render was too thick. They are 1930 s built ex council houses with concrete type thick textured render, several houses in the street are the same.
Has any one heard of this causing extensive mould?

More likely that it isnt being ventilated properly, if they are drying clothes on radiators all winter with no windows open then where is all that water going?

Sounds like a condensation problem to me.

Is there trickle vents on the windows? If so make sure they are open and get a fan put in the bathroom and advise the tenants to keep the door shut and open the window a bit while running a bath.

If you have a chance in the future then consider having the inside of the exterior walls insulated, as condensation simply happens on cold spots.

I would have vent installed then decontaminate the whole house.