I had trouble with mine fogging after I opened mine to paint the insides... Found a good cure was to take bulbs out & blast a hairdryer through the main beam hole & re-seal...
Obviously you've got quite a bit more moisture in yours so maybe try that & then leave in airing cupboard or next to radiator overnight as Skinner says & see how it goes. Will also help the sealant dry but don't use too much, I made that mistake first time round, just a small bead will do!
Of course, if you're planning on spraying the inside of your lights at any point in the future, prob best to think about doing it now... Cover both tasks in one go...