Captain Ishida Hisashi
If anything, the grenades had a rather lacklustre effect. It was as expected, as bodies were piling over them before they exploded. If a single Kyonshi were to outright lie on top of a grenade, the resulting blast might not even kill the unfortunate reanimated corpse much less do any damage to everything around it, as the brain needs to be destroyed.
As everyone was climbing over the SUV barricade once again, Captain Ishida and Sergeant Maiko covered them just like they wanted, though the medical officer would have done it anyway. It was his job to protect these poor people. Long before he'd been forced to join the military, he had sworn an oath, after all, to heal or at least do no harm. It was an oath of western sources, now coming back to its roots and it was paying off. He had his own beliefs of course.
After the last of the evacuees reached temporary safety over the pathetic wall, the two JSDF soldiers climbed over it themselves. "Go to the top! We calling for extraction! We will cover you!" Before ascending the concrete ramps to the top, however, Captain Ishida knew that he couldn't just leave the undead alone now. They were already beginning to regain their momentum. Many of them won't even be able to stand, but they will crawl, wriggle, struggle towards them, no matter what it took. That was the advantage of the dead. They may crawl at a snail's pace, they may trip over each other after the blast and shamble at the pace of a dying old man, but they will come.
"Maiko, trap the barricade." He ordered his medic in Japanese before turning to the rest and asking them to carry on, "we go to the top, now." After a while, he finally had time to read the nametag of the local soldier he had saved, "Ibanez, escort civilians to the top."
Sergeant Maiko acknowledged the command with a rather mischievous look and smile on her face before looking around for whatever resources she could use to kill a whole bunch of Kyonshi, and her eyes finally settled on the SUV itself. Opening the fuel hatch and cap, she stuck her remaining grenade in it. Using an elastic bandage, she managed to improvise a triggering mechanism that would push the lever and detonate the grenade. For the pin, she simply loosened it and attached a very long surgical thread to it, tying it to the railing to the side of the ramp. Once tripped, it would blow the grenade and the SUV's fuel tank. To add more potency to the trap, she'd left a jerrycan of petrol she'd found by the SUV after pouring half of the content all over the place.
The resulting explosion will destroy far more of the Kyonshi, create a wall of fire and distract them, providing more than enough cover. Which was why she promptly booked it and joined everyone else who were running up.