There are a few companies that are doing clinical trials in humans using drugs that may restore hearing. They've done a good job of keeping the results under lock and key so far but one of them (Frequency Therapeutics) might announcing some preliminary results next month. I've linked a press release from a few months ago. As there are several companies attacking this problem from different angles, and an explosion in clinical trials, you wouldn't be crazy to be optimistic. If by luck any one of these drugs turns out to improve hearing by 10db or so, you might see the it on the market in no more than a few years.
YMMV but it might be something useful to try with your wife.
In this case the sound that arrives at the eardrum does not conduct through the middle ear bones to the cochlea.
Wax will only cause a slight drop in hearing thresholds.
This can be determined with a standard hearing exam.
Recently tried a demonstration at SF's Exploratorium which involved biting a metal bar, and the result was incredible!
Most bone conduction headphones I find when searching (eg AfterShokz) appear to rest against the bones around the ear, so I'm not sure if they're as effective.
Still, it's software which you can't manage yourself. Any Oticon people on here, handling of the release of S w/ feedback shield issues with high pitched voices was done quite poorly.
There are some large and fairly extensive genetic panels that can be run within months now for a few thousand if insurance doesn't cover. Unfortunately they don't have the variants causing my loss. Looking at full exome sequencing at Stanford but insurance is balking and it's 10k.