Submerged Units Revealing Eachother

For some reason submerged units can't have abilities. (Thanks Blizzard.) I have the Gnomish sub and Troll submerger in my map and I need them to reveal eachother when they are in say, within 500 units of eachother. They should also only reveal "Burrowed" units, not invisible units on land. I say burrow because there is no special sea classification for submerged units because they aren't suppose to be able to move. I tried every form or upgrade and default active ability for revealing before I realized that submerged units cant have abilities. So obviously what I need here is a trigger or some JASS. Keep in mind it needs to be multi-instance for atleast 10 players, so JASS will likely be the easier choice. If possible it would be nice to get the submerged units to display a passive icon in the command box, just for the illusion that it really does have the ability.

a reveal ability wont work because the detection type (invisible/borrowed) basically does nothing, invisible will reveal both types.
if u dont mind submerged submarines detecting invisible units (on land) then use a dummy unit, create it when the submarine submerges, and remove it when it merges back.
else i dont think it would be possible unless u make your own invisibilty system.

What about not actually using submerge, and using a modified burrow instead?

Well yes I thought about the dummy unit, but I only know how to do triggers and I can't make them multi instance. I need someone that knows JASS to help here.

Multi Instanceability is quite possible in GUI as well...

not for this case, the closest thing would be custom values and loops and that would be horribily inefficient

Well could one of you test some sort of system for me? My computer is messed up right now and won't be fixed for awhile. I was hoping you would do it Lord Vexorian, since I have the caster system 11.7 and most of the custom spells in my map are yours. I am not that skilled at JASS yet.

So can anyone help me with this?