I can't imagine there'd be a rule against naming an absent player on the bench, but why would you even name an absent player on the bench in the first place? :confused:
Edit: I've not been able to find this season's Participation Agreement online but have been able to find 2011's, which I would imagine is pretty similar, if not largely identical: https://www.fai.ie/agents_info/2011P...nAgreement.pdf
There didn't appear to be any express obligation upon named substitutes to be in attendance in 2011's agreement at least. The regulations covering team sheets, substitutions and technical officials can be found in the document linked to above from article 20.10 on page 41 onward.