Importing graphics into Keynote

I'm creating a presentation for a client in Keynote.

They have a very specific colour palette, which I have used throughout the document.

I have created elements within the document which I have applied the colour palette to without incident.

All good so far.

Unfortunately, whenever I import graphics into the document, the colours (of the imported graphics) are all over the place.

I'm generating the content in Adobe Illustrator and Adobe Photoshop, both using RGB colour spaces.

I've done a bit of research and I understand it's something to do with the monitor profile and that everything imported into Keynote is converted.

I've updated the profiles selected within each program to Adobe RGB (1998) to match the profile in the display control panel, but it doesn't seem to make any difference.

Has anybody come across this problem themselves?

Am I doing something wrong?

Any advice would be much appreciated.