For the first question: yes.

The issue is this isn't the same concept as mosquito efforts where genetically modified mosquitos are released and meant to replace the natural populations. So we won't be ridding the world of disease-causing bacteria ever.

This isn't practical for bacteria. There are several limitations that these mosquito effort don't have(one obvious one is bacteria aren't buzzing around us for us to easily detect haha)

For the second question: Bacterial conjugation (genetic transfer between bacteria via direct contact) is definitely a possibility for certain bacteria with these capabilities. Also, it is typically plasmid DNA (so DNA from a tiny "chromosome" versus the main bacterial DNA) so these genes would have to be on this plasmid to be transferred typically, and it is likely not a part of this DNA, but who knows (I haven't looked into this bacterium). However, it isn't like a domino effect or a wave where these genes transfer exponentially. So if this did occur, it would likely remain a significant minority of the bacteria (like 0.0001%) because these would likely be engineered at a massive scale to perform the function. I also doubt where/when this occurs there will be a significant natural population of these bacteria. If there is, they could/would likely be killed before repopulation begins.

I haven't looked into this exact use so I don't know how they are planning to go about everything so my comment might be missing some key information.

Basically, these things are easily accounted for with bacteria (with some exceptions depending on the bacterium).