Sikaflex 290dc and Sikkens on a house verandah

Hi all, first post so be nice :)

Looking for advice and wondering if anybody is charatible enough to provide......

I have been renovating an old queenslander for about 6 years. The front verandah had been enclosed and I wanted to open it up again. I needed to waterproof the floor. After much research, I pulled all the boards up and layed them down with an 8mm gap that I filled with Sikaflex 290DC to form a boat deck. We contacted a floor sanding company to sand and finish the hardwood boards. Sikkens was suggested as the preferred product. The verandah is open but under the house roof. The floor is now waterproof by the way.

After sanding and first coat application of Sikkens Cetol deck the finish looked spectacular however after many weeks the product layed over the top of the Sikaflex refused to dry and filled with contaminants (dust...). Some months later the floor sanding company have returned to resand the boards and apply Sikkens HLS which is supposed to go off in lower UV conditions (as specified by the Sikkens Rep). It has been almost a week and this product also looks like it is not going to go off.

Can anybody suggest what may be going on here? Sikkens seem to be at a loss as to why this is happening as it is these products that are specified for boat decks.

Any alternatives? Apparently some products break down the sikaflex so are not compatable.

Thanks for any help.

Arran