The generator matrix

 1  0  0  1  1  1  1  1 2a+2
 0  1  0  1 2a+2  3 3a+3 a+1  1
 0  0  1 3a+3  1 2a+3 a+3  2 a+1

generates a code of length 9 over GR(16,4) who´s minimum homogenous weight is 22.

Homogenous weight enumerator: w(x)=1x^0+432x^22+468x^24+864x^26+1296x^28+1008x^30+27x^32

The gray image is a code over GF(4) with n=36, k=6 and d=22.
This code was found by Heurico 1.16 in 0.093 seconds.