Yes, you can use Sudocrem with cloth nappies. However, there may be a downside to using Sudocrem with cloth nappy. If you use Sudocrem with a cloth nappy, it may cause the nappy to resist urine which may lead to leaking.
One of the sure ways to keep the nappies clean in situations like this is by utilizing a fleece liner between the nappy and the Sudocrem.