I agree with the above post.
It matters not - most outworkers are people who apprenticed with one of the best firms, then went freelance in their specialist area. Does it matter if your Holland apprenticed stocker made your Holand's stock the month before he left them (as an employee) or six months after he did (as a free-lance)? He's thae same bloke working to the same standards.
Westley Richards, Purdey and Holland & Holland all have factories - David McKay Brown seems to do it all in house too. Churchill, Atkin, Grant & Lang, Greener have facilities to do most things but out-source as needed. Twas always thus.If you have lots of orders you outsource to the trade to keep filling them.
Think about it - most firms in other walks of life do the same.As long as the quality control is set and met, the product is the same product.