That’s a large part of why DM was nerfed the way it was. It’s not that much of a factor compared to having enough lethality to secure the kill if that ability is on CD or if people just aren’t fast enough on the trigger.
Accretion goes through matrix precisely because matrix was problematic. Relying on such a poorly designed mechanic is going to make things worse, doubly so because characters that can be DM’d can so easily be switched off. The threat of a pre rework Brig swap was enough to render dive unviable.
So how about we don’t mess with kinetic grasp, give him immunity to his own splash damage, but make it so Accretion stun is actually zero within 10m range.