I think you're using "Muslim" as a blanket term. There are varying degrees of piousness in Muslims as there are in any other religion. (something I admit took me many years to realise!)
Some Muslims would appreciate a bottle of Scotch, some would be dismayed or embarrassed with such a gift.
Some Muslims would laugh their head off at a saucy card, some would be offended.
I don't think his marital status would come into it at all, unless you were choosing something flirty, in which case, he's liberal minded and probably is not choosy about presents.
If he's so radically Islamic that his colleagues have to tread on eggshells, more fool him for choosing a non-Muslim working environment without being prepared for non-Muslim customs.
If you don't know his favourite pastimes can't you drop hinty questions about them?