Yes, you are absolutely right- the yellow sawhorse is not Playmobil. It is is actually made of very flimsy plastic!
When Mr Raven saw the advertised ‘ladder connector’, he decided that we needed that one too, whether or not it is Playmobil. (All searching for it has found nothing, so I’m now assuming it is not Playmobil either.) So he bought that collection of roadworker/construction items.
A non-Playmobil figure also arrived.

It has PlayBig-type hands, but is otherwise nothing like PlayBig. Does anyone know where it came from? Its source might even lead to the solving of the mystery of the ladder connectors. I don’t think they are PlayBig, because, as far as I remember, PlayBig ladders are white, not pale brown.