Well over in The Netherlands H&M have been afforded VVIP status which brings much enhanced security. They're not, however, meeting the Dutch royal family. Apparently.
If this is true it's interesting. It would seem that their status is elevated in NL which would signal to me that the Dutch don't want to run the risk of anything happening to H&M on their soil.
I know there's a lot of security around the location of Invictus too, more than for other events apparently. You can't just buy a ticket and go, you have to bring ID too and can be required to show it. While it's obligatory to carry ID in NL, you don't need to show it to get into sporting events.
I wonder too if foreign royal families can't be seen in contact with H&M for fear of being seen to raise their "non-royal" status. Katherine went to NL a couple of years ago and spent time with the King and Queen of NL. Regular people obviously don't and H&M are private citizens, so wouldn't ordinarily meet the King and Queen. Given what the Invictus Games celebrates, however, I do wonder whether Willem-Alexander and/or Maxima will "pop-in". The level of security would make it easy for that to be arranged.
Also, as an aside, the timing of it is a bit sad for competitors. The Dutch schools have Easter weekend off, but that's it. They have school next week and following two weeks off. This is reflected in ticket sales which are sold out until Monday but Tues-Fri all sessions are still available.