Hi,
I've wet anddry cleaned in the past and you are right , dry cleaning is just not going to be very effective.
It then comes down to deciding on your customers expectations , are they prepared to accept a little pile stiffening as the price for a clean suite or are they looking for perfection.
Depending on their response i would clean carefully with HWE , water not too hot or leave alone if you expect possible trouble.
Is the pattern of a flower.
Cheers
Doug