I wouldnt rush into clipping him just because you are going on holidays. Remember once you clip him he will be unable to fly for up to a year and not just for the 2 weeks you are on the cruise. I have left my greys in their big cage while I was away. I asked the person who was minding them not to let them out at all. They fed them, gave them water, chatted to them and played with them, all without ever taking them out of the cage. I did this for 2 reasons. Firstly I was afraid that the minder might get bitten as the greys didnt know her very well, and secondly I was afraid she wouldnt be ablet to get the birds back into the cage safely.
Their cage is big enough that they can flap their wings and stretch inside the cage and I felt I would rather they stayed in the cage and the minder and the birds were safe and unharmed, than let out regularly and run the risk of someone - bird or human getting hurt :ohmy: !
This worked well for me and could perhaps work for you too?