You don't have to worry at all about gelatin doing anything bad flavour-wise, even after long periods. It doesn't add any flavour or have any negative effects. You can bottle beer that has been fined with gelatin and age it with no ill effects
I have a Munich Dunkel that is currently cold conditioning. I'll be away for about 2 weeks, then planning to bottle as soon as I'm back. Would it be ok to leave it after adding gelatine for this period of time prior to returning and bottling?
That'll be fine. Even though it should be lovely and crystal clear after that time, there will still be enough yeast left in suspension to allow carbonation in the bottle. Maybe it could take a little longer to fully carbonate (maybe 3 weeks instead of 2?), but shouldn't be an problem