Agreed Marv about the water issue. While liquid oxygen and hydrogen can be recombined to make water the process in not as easy as simply pouring the 2 elements together, the same as sepperating the 2 elements then compressing them into a liquid state.
Carrying water would be a great expense in weight to boost ratio but that would not be the ultimate problem when water is exposed to negative atmospheric pressure IE a vacuum it almost instantly boils away.
My suggestion of using a 2 part expanding foam also depends on having at least a neutral pressure which would require some form of barrier. Possibly in the form of a thin poly film covered with the regoliff. A 3rd part would have to be included such as a gas may have to be included to serve as a catalyst as it was injected in order for the chemical reaction to start. But we have the means to conduct such experiments in vacuum chambers. The process could be tested and perfected aboard the ISS.
Yes the dark side of the moon could yield untold benefits aside from having to over come the extreme cold the lower solar radiation could be a huge plus.