Here in the UK, the recommended temperature for hot water is 60°C (140°f), to reduce the risk of legionella, although it also should not reach 65°C, as that can quickly cause bad scolding. This dates back to us normally having hot water storage cylinders. These days, with most homes having instant hot water from combi boilers, it probably doesn't need to be quite as hot.
I wouldn't know what temperature is recommended in the US, and I guess with a rented property you might even need to consider the risk of litigation in case some fool manages to scold themself!
Our washing machines have always had a heating element to achieve the set washing temperature, these days virtually all are cold fill only, so they solely rely on their element.
I think chlorine based bleach and the peracetic acid produced by oxygen bleach + TAED should be equally effective at sanitising the machine and either would be effective at destroying bacterial spores too, which will stop it quickly coming back, so as hypochlorite bleach is more readily available, I would use that. Oxygen bleach has a few minor advantages, such as the machine won't smell of chlorine after the cleaning cycle.
When used as an in wash additive, oxygen bleach is colour safe (although with repeated washing, it can cause fading in some dark colours), less damaging to fabrics, and breaks down to harmless components. It should not be used on silk, or wool, or on fire retardant treated fabrics. I'm surprised if the tenant is a germaphobe, that they don't use something to kill bacteria, like a laundry sanitiser or oxygen bleach with their detergent.
