Are the legs different color maybe?To be honest I have no idea how people tell them apart. I know I sure cant. Every time I'd seen a Vorwerk I was like, oh hey, a golden Lakenvelder...and then I found out about the existence of the Vorwerk breed and now I'm just like...yep, it's one or the other.
The waters are muddied by the fact that people often refer incorrectly to Vorwerks as golden Lakenvelders (which are a thing, as you said) AND the Lakenvelder was used to create the Vorwerk so...fun times.
I think the main difference is the Lakenvelder is an egg breed, but Vorwerks are dual purpose so if you pick one up...maybe you can tell, lol.