diff --git a/holoviews/core/util.py b/holoviews/core/util.py
index 04543cfdef..044e20ad38 100644
--- a/holoviews/core/util.py
+++ b/holoviews/core/util.py
@@ -2352,7 +2352,7 @@ def lazy_isinstance(obj, class_or_tuple):
     obj_mod_name = obj.__module__.split('.')[0]
     for cls in class_or_tuple:
         mod_name, _, attr_name = cls.partition(':')
-        if obj_mod_name != mod_name.split(".")[0]:
+        if not obj_mod_name.startswith(mod_name.split(".")[0]):
             continue
         mod = importlib.import_module(mod_name)
         if isinstance(obj, functools.reduce(getattr, attr_name.split('.'), mod)):
diff --git a/holoviews/operation/datashader.py b/holoviews/operation/datashader.py
index b8b20821b2..d75c05ccca 100644
--- a/holoviews/operation/datashader.py
+++ b/holoviews/operation/datashader.py
@@ -35,6 +35,7 @@
     Dataset,
     PandasInterface,
     XArrayInterface,
+    cuDFInterface,
 )
 from ..core.util import (
     cast_array_to_int64,
@@ -318,7 +319,7 @@ def get_agg_data(cls, obj, category=None):
         if category and df[category].dtype.name != 'category':
             df[category] = df[category].astype('category')
 
-        is_custom = lazy_isinstance(path, ("dask.dataframe:DataFrame", "cudf:DataFrame", "cudf:Series"))
+        is_custom = lazy_isinstance(df, "dask.dataframe:DataFrame") or cuDFInterface.applies(df)
         if any((not is_custom and len(df[d.name]) and isinstance(df[d.name].values[0], cftime_types)) or
                df[d.name].dtype.kind in ["M", "u"] for d in (x, y)):
             df = df.copy()