It won't self attach to hardscape, but it happily grows without substrate. You could glue it but I'm not sure how long that will last before the glued parts rot and it lifts off though. I've done it with some Hydrocotyle Tripartita mini - which isn't epiphyte either, and the pieces are staying put so far (4 weeks). You might have more longer term success tying it to wood with fishing line though.
@Geoffrey Rea has managed to get it to grow attached to rocks due to having moss mixed in with it that secured itself to the rock, and therefore held the Cuba in place. I'd link to it but I can no longer find the thread strangely.
Basically the plant will feed through water, so it can easily grow "epiphytical".
It can not attach to smooth surfaces, though. I have had cuba Hem. grow, twisted inbetween very branched wood (ex. Azalea aka 'bonzai') and it wilingly attach to rough rock (ex. Lava). Adrie Baumann (Aquascaping symphony) have used these technique often.