I feel like there would be a LOT less demand for a Glock bowie than the Glock field knife.
For one, militaries would not buy it.
For two, bowies are not even a thing every knife collector feels he needs to have.
I don't think it would justify the expense to design, tool up and produce it.
The fact that Glock marketed their Steyr AUG bayonet as a "field knife" and made it widely available for civilian purchase is pretty unique. This angle wouldn't work for a bowie, as they wouldn't have the military foundation to start it off. Probably, civilian sales are just icing on the cake.
What they did instead was to use the same model, and make their nice little shovel available, again after establishing the military foundation. It seems like Glock is hesitant to branch out in edged tools the way they did in guns. In guns, they have a few models that they sell to the world's police and military market. I'm betting that they branched out into civilian models only because they could share so many parts with the police and military models; it made business sense.
What they might be able to do is to make a basic pocket knife to sell to militaries & police at a lower cost and complexity than the typical SAK. (just like they did with pistols 40 years ago)