The main problem to visit U-995, as I see it, is that we would need the full day to go there and back from Copenhagen. That means that we should be in our hotel at Copenhagen the night of the 15th, then spend the whole 16th going to Laboe, visit the museum and back. We could rent one or several cars for this.
The other alternative is flying to Hamburg, then going to Copenhagen and visit U-995 on the way, as Neal suggests. The problem for this alternative is that you would either need to go back to Hamburg to pick your flight when the meeting is over, or have your return flight start from Copenhagen, which is usually more expensive.
Last but not least, Hamburg has many less combinations as it is a smaller Airport than Copenhagen, and for example there are no direct flights from Madrid or Barcelona to Hamburg, so I would need to pick at least 3 flights to arrive there
I'm inclined to think that the best alternative is therefore making a full day trip and back from Copenhagen. Only that way we will have a relaxed visit and be able to enjoy everything plus then start the meeting the 17th perfectly on schedule
