Artifacts in print - Please help!

Hi all,

I will apologise in advance if I am in the wrong community here, but I desperately need help, even pointing in the right direction of a community that could help would be great.

I am starting a business where I am getting a bath mat made in China. I am not sure of the machine they are using but this can be found out if needed. They recently produced a bad sample with lots of artefacts, I noticed the BMP file the used to create the sample was set to RGB colour mode.

The last sample they did that was much better was set to Indexed colour mode. Do you think this may be why the current sample was so bad?

I have attached images of both the good and bad samples.

The mat is only 2 colours, so maybe bitmap colour mode would be even better? Any help would be greatly appreciated with this. I'm in the UK and unfortunately don't know any UK based bath mat manufacturers.