It should work but you'll probably draw more attention to yourself than a garden variety refundable ticket for gate pass purposes. They'll know you're in the lounge and may try to coddle you a bit in terms of making your flight.

I've done it many times with domestic refundable tickets so I can use Pre and access the Club..but never for an IFL. I don't think I'd want the attention.. plus I'm a Club member and using a refundable ticket to access a Club doesn't get me any other benefits that I don't already pay for.. but using an IFL does.