Yes, both techs work, and reanimated ships also re-spawn at your home world. Also, ships at your home world will follow rally point commands, which made it slightly hard to tell when it started working, and also started sending ships through a treacherous path.

It's interesting to see it all working...

• Because of the low percentage, its not overpowering, but it does give an economic advantage. 
• Because it resurrects ships you already made, it's not like the other factions' ship summon abilities... it actually gives you something useful (afore mentioned reanimated ships the only exception, but you can just not take the ability)
• Because it's not tied to a structure you can't stop it... Assuming you have a home world. Actually, I don't know what happens if you don't have one... 

The combo rez techs we were all wondering about don't seem all that great, but every little bit helps... One thing to note though is that reanimated ships are temporary... unless they've been returned to you home world... so, suicide runs with your zombies are a good idea... or probably feeding your titan

Since I patched rebellion to 1.1 I noticed that return of the fallen happens without having to research it.  However it also removes the resource purchase cost from your resources, basically like you bought it again except that you have no say in the matter and it builds instantly.  Its fine if you need a ship in a hurry, its a drag if you are trying to save up to pay for something else.

I ran some tests in the debugger and didn't see any evidence of this.

Are you sure you didn't have a starbase deploying somewhere or a drone host building mines on autocast?

I'm not sure why you asked about those things since I can't see how they would cause the issue.  Here is exactly how I noticed it. 

I was going for the harmony research achievement.  I was playing the point blank map with pirates inactive.  I did no research other than harmony research (including no fleet research) but had not done the return of the fallen research.  I had my capital ship away from the homeworld going after unowned planets and a group of base frigates at the home planet.  The AI was attacking my home planet so I was queuing up frigates to rebuild as fast as they were destroyed.  Every so often a new frigate would appear next to the planet (nowhere near the factory) and occasionally one would appear at the planet and one at the factory very close together in time (too fast to have both been built).  Perhaps it isn't return of the fallen causing it but the way they appeared looks exactly like return of the fallen and I was playing advent rebels.  I have not seen it happen with any other race. 

I also thought I had seen something like it in another game where occasionally I was finding odd frigates at the home planet rally point when I did not remember building them, but I was not paying enough attention to see what was happening that game or if it was because I had simply lost track of some ships.  It wasn't until the games I played going after harmony researcher that I saw it in detail.  Also, since the harmony researcher achievement was not triggering for me I actually did it twice and saw it happen both times.

I asked because you said resources were being removed because of ROF which they are not.

New players tend to forget mines and starbases may be delayed until resources become available and then they report bugs where resources mysteriously disappear, hence the question.

Advent rebels by default start with a 5% chance to re-spawn frigates on death. The only thing affected by this is your fleet supply which the previously deceased frigate was already using, so that part is a wash.

You can of course scuttle an unwanted ROF frigates which will net you FREE credits and resources.

Oh I see.  I did not realize that ROF happened at 5% without any research but now that I look at it I see where it says the level one research goes from 5% to 10%. So that explains the ships re-spawning.  I actually did not see the resources subtracted when a frigate re-spawned but now I understand why you asked what you did as well. 

What I saw was my resources drop while I was saving for something.  Close to that time I also heard the "strength in unity" twice close together and I only had a single frigate factory so then I went to look at my home planet and saw what appeared to be a frigate coming from near the planet and another from the factory.

I can't think of anything that early in the game that would cause the resource drop like I saw but I am familiar with the phenomenon of seeing that happen when you tell a ship to build a starbase and it take a little time for it to get to the location.  That early in game though everything I can think of subtracts the cost when you queue it.  But it may be that something like that is exactly what happened and I erroneously attributed it to the ROF since I also didn't think ROF was supposed to be occurring at all.

I tried to reproduce this but I did not see where resources were being removed for the free 5% ROF.  In fact I saw the free 5% ROF not reducing resources when frigates re-spawned.  If it wasn't a starbase and it wasn't mines what could I have queued that waited to charge?  It could be that I was also un-queuing things around the same time because I was in combat and may have changed my mind about what I was building and researching.  Maybe if I un-queued something in a strange order and then re-queued something I could have recreated that resource drop phenomenon like when the starbase does the delayed build?