I have heard the rooks towers takes cital upgrades as the the building health and tower offence.
which is it devs. yes or no
Actually cit upgrades do effect towers. And yes ive tried it. Summon a tower, it has 1200 health, buy the first upgrade it goes up to about 1400 health or so, can't remember accurately the numbers but im like 95% sure that cit upgrades effect rook towers, because ive also seen rook towers regen themselves with the health upgrade.
No, they don't benefit from Citadel upgrades. This has been discussed, tested, and refuted several times already.