The "usual suspect" when color is off is that they did not flush out all the old coolant, so you have some old and some new. Not a big deal if staying with the same coolant, but it IS a big deal of one is "regular low silicate for diesel" coolant and the other is an OAT-based coolant.
I had this when we bought our current coach. Previous owner paid to have system flushed and change from regular to OAT (Cat ELC). Me, being a (not so) trusting soul, I pulled a sample-- color was not strawberry as it should have been, but strawberry with a green sheen! So, I flushed it myself and went back with ELC.
For techs working on trucks, having this problem on a motorhome is not uncommon. Instead of 6' of heater hose, your motorhome has 50+'-- much harder to flush.