Urgent need help with bearing grease!

[Deeds]

Hey everyone, I kinda need some urgent help, I have a 2015 keystone laredo 23rb... I bought it last year from my parents who bought it, had it delivered to my place and due to health reasons prevented them from using it even once... I bought it last year from them and had the dealer go over it but looking at my receipt and giving the dealer a call the bearings were overlooked! We leave first thing in the morning and now I've realized that for 4 years the bearings have not been greased granted the trailer has less than 1000 miles on it I'm struggling with what to do! I dont know how to disassemble the the axle to clean and repack, I can add grease to the ez lube fittings though! Curious do you guys think 4 years but less than 1000 miles the preexisting grease is good to run or should i add some? I feel like i know the answer but now I've been told if i dont know what's in there it's bad news to add some because some greases dont mix well. I would add lucas red and tacky if y'all think that's a good thing to do. No dealers were able to squeeze me in! And I was told it was done so normally i wouldn't neglect things like this!