1st, I was not aware that anyone, including DW, was using MM anymore. Are you sure it is a MM?
2nd, the pushers that DW has been using are the same as those sold by ofrei.com & other watch parts houses. So, if yours are too short, simply purchase another set (you cut them to fit your movement).
Anyone who works on chronos (I am not accepting any new work, so please do not PM me) can clean/lube/adjust a MM, but it is nearly impossible to find replacement parts, which is why they are not generally used anymore. Once a part is needed, your only real option is to replace the movement (I believe, but cannot guarantee, that a 7750 can be made to fit the case).