Are these dents repairable using hot water and a plunger?

That dent looks too big for a"plunger" repair. I think the plunger method is more for hail dents which would be much smaller ( hopefully). Hail dents I have had are more like 10 to 20% the size of the dent in the second photo. I have heard of fixing hail dents with ice in hot weather but not hot water. However, it is probably worth a try because a body shop will be expensive. As commented , it looks more like a "push from the back" job.