Thanks for your question as it tells us so much about you and your relationship. Congratulations on being so helpful!
I rarely use what we might call 'bags' because I irrigate. However, I do use irrigation sleeves, which I wash out and hang up as you describe, so the principles and practice will be much the same.
Once I have washed it thoroughly, I spray it with an antibactial spray which is the same type as we use for the everyday surface cleaning, I then hang them on a hook in the shower cubical. This, not only prevents bacteria but also cleans. My sleeves usually last a month (using them every day). They would last a lot longer, but I think a month is long enough! And, even with the washing and spraying, they will begin to stain and have a slight smell after that period.
Hanging them in the warm will dry them off quicker, but the downside is that any heat encourages that stale residual smell.
Prior to my present routine, I used to simply wash them out, spray them, roll them up and put them in a sealed container. This worked fine for years, and certainly contained any smell until the container was opened. As with anything that is sealed away for any length of time, any smell will accumulate inside the container and be released when it is opened.
I have no experience with condo's, but have you tried hanging them outside (in the fresh air to dry)? Even if this is using just an open window, the outside air will take any residual smell away from the inside of the property, and something as small as a stoma bag would not be an excessive adornment to a domestic window.
'Outside', is what we used to do with any dog towels and equipment that needed cleaning and drying. At least the smell did not linger inside the house! If you don't like the thought of other people seeing stoma bags hanging on the line, or out of a window (or ventilator) then hiding them inside a recognisably 'acceptable' cloth sleeve might be the answer. (dry-wipes made into a bag would do it, as would the bags that are provided by some supermarkets for vegetables, pillow cases, handkerchiefs, shirts, hairnets, underpants and a whole range of other things would easily disguise a stoma bag whilst drying outside).
Alternatively, you could use one of those large 'hoses' that are used for ventilating tumble driers, I often see those dangling out of windows and everyone knows and appreciates what they are for. Indeed, you could even rig up your fan so that it blows air through the tube and dries off the bag hidden inside.
In a couple of places around my house, I have different sizes and shapes of ventilator fans and I feel sure that whatever type of windows you have, somewhere there will be a fan to fit.
I hope some of these ideas might help you to think around the problem and come up with a suitable solution.