I think this is the bike. ACTUAL PHOTOS OF [MENTION=374193]Dave Horne[/MENTION]'s bike would be nice.
https://www.vannicholas.com/touring-bikes/deveron
It appears as if the frame is designed for flat (MTB/Hybrid) bars, meaning it is a long frame, and sized more like a MTB than a road bike.
The market for their 57 cm frame must be very narrow.
The difference in length between the 47 and 52 is only 2cm. I'm surprised you can't compensate with a shorter stem and swept back bars.
You should have adequate stand-over (and once up on the seat and pedals, stand-over doesn't make a big difference).
I agree, while the shop should be familiar with manufacturer recommendations, you had the old bike to measure, and were with them looking at specs.
You might have been able to reject the bike when it came into the shop. But, now you've had the bike for "a few months"... so it is a used bike, and falls back on the shop policy. REI, here in the USA has a 1 year satisfaction guarantee, but not all shops do that.
Because of the geared bottom bracket, stripping the frame for parts is probably not a good idea, unless there are a few parts you would wish to downgrade (front dynamo, racks, etc).
Don't be overly concerned about aesthetics. Make the bike work for you. If it doesn't, then buy the right one.