How can I package durian flesh so that its fragrance cannot be detected?

I would recon you´d need a glass or metal container, as aroma-molecules can diffuse though plastic.

This is basically the same Problem users of certain "herbs" have, so naturally there is a lot of information available if you look at the right places

If freezing is an option, that is probably the direction I would suggest. Most markets I have seen it in sell it that way as a matter of fact. I would still wrapping and maybe a sealed container as I do not believe freezing will completely eliminate the smell especially if it is not they whole fruit. The faster you can freeze will reduce how much smell may spread until it is frozen. I would tend to assume that colder is better as well. I would consider if you have it available to use dry ice to initially freeze it to prevent having other items or your freezer capturing the smell.

I worked with someone who especially liked it, and it is a very interesting fruit. We had to finally ban it from the office though as the smell earns its reputation.

Maybe I am hurting unstated assumptions behind the question, but: you could try making canned durian.

Smell means that volatile substances are being emitted from the fruit into the air, and land on your airways' mucosa. Canning jars for home use underpressurized air to seal. This means that they are not just sealed the way plastic bags are, there are no molecules travelling from the jar to the outside at all - if there was any hole for molecules to go through, they would go into the other direction, from the pressurized atmosphere to the underpressurized jar. So, no air exchange. And the glass is impermeable even for small molecules, unlike the plastic of sealing bags and the like, which may let some air through.

The solution still has to be tested for real-life suitability. One concern is that the underpressure is achieved by having the hot jars release some of their contents into the canner - mostly air from the headspace, but small leaks are expected to happen from a few of the jars out of a batch. If the jars spend several minutes in a durian-scented water bath, it may be that they continue to reek for a long time after being taken out. So you would have to test - preferably with extra headspace. Also, since there seem to be no official recipes published on home canning durian, you'll need to measure your own pH and adjust if needed.

You could use a heat sealing machine with heavy duty vaccuum bags.

This is a bizarre answer and may not be practical, but if you seal it well in plastic bags and submerge the bag under water it might help. This, of course, is the principle behind toilets ;)