Thread: Sticking tiles back on.

Hi Guys
I am a newbie, a bit of a DIY buff, woodworker and a Mr Fixit, but this has me beat.
Our three year old townhouse started to rock and rumble the other week. The house next door was being demolished for a new town house development. Welcome to medium density heaven! I shouldn't complain, I live in one!

After a couple of days, they brought in an excavator with hydraulic jack hammer, to tackle the concrete first floor and double cavity brick walls. One almighty bang and the house fell in a heap. At the same time, a dozen 300mm square terracotta tiles detached from my balcony edge and buried themselves in the garden!
After recovering from the shock, I got out the ladder and inspected where the tiles had detached. I found a 10mm thick strip of cement board coated with about 2mm of a rubbery grey material. The grout had gone the way of the tiles and it was obvious there hadn't been much holding 'em up!
My problem is, what do I stick 'em back up with?
Obviously I have to get new tiles, but it's clear that the rubbery surface is not compatible with the original grout.
So, what do I do?
I tied a smear of turps on the rubbery stuff. No different.
I tried acetone and was ignored. It is too tough to scrape off, so how do I decide what might suit as a good bonding grout for the new tiles?
I have smeared some outdoor spakfilla on to see if it will bond, also coated a small area with bondcrete but it peels off.
The demolisher, bless him, has offered to do the repair but, demolishers do not, good builders make!
Anyone any ideas? They would be appreciated.