I just opened this second gearbox up to do the filter and re-seal the sump. While there may be red ATF which conforms to the spec, in 100% of two cases, it is indicative of other heinous bodging. In my case, sticking the sump on with bathroom sealant. In this one, forgetting the o-ring on the filter
They also appear to have lost one of the bolts for the filter so used whatever they had kicking around which was much longer than it should be, and did the same on the sump
Now I probably have to pull the valve body to make sure the over-size bolt didn't crack it.
Oh, and also the wrong oil in the diffs too. After only 2 years it's as black as treacle so it looks like they used GL4, not GL4+.