Hi Walter,
I've never used the Hydrofera, but I have used the Ostoform. While an interesting idea, it didn't have any real benefit in my situation and I don't expect it would help much with a recessed stoma. You're going to have to get your wife's peristomal skin under control before you can really evaluate any type of fix. I'd start changing her barrier every day, and during each change apply a Domeboro soak (or any aluminum acetate topical astringent) for as long as possible before installing a new barrier. Thirty minutes would be ideal, but even ten minutes would help. The problem is there really aren't any products out there designed for stomas that are retracted. In that situation, there's really no way to keep output from getting under whatever is applied topically to the skin, be it a ring, barrier, etc.
What you could try after the soak and with the skin completely dry would be a breathable waterproof film dressing like Tegaderm. Apply it sticky side towards the skin and then put your barrier on top. Change the barrier the next day to assess how the film is working. If it looks good, repeat the process and try two days. If it only looks marginally better, then stick to one-day changes and continue with the soaks until the skin has healed.
Also consider what Iggie is saying, as it makes sense. As long as your wife's stoma is at or below skin level, she's going to be dealing with all this bullshit indefinitely. The only real fix is to have the surgeon pull the stoma out a bit and re-suture it. Most times it could almost be outpatient, but they want to keep you overnight just to be sure. Other times it's more involved if there are adhesions or other issues preventing them from simply pulling the stoma out a bit. So have the discussion with your surgeon. Let us know how your wife is progressing.
;O)