diff --git a/dsv4/kernels/router/nvfp4_fused_router_kernel.py b/dsv4/kernels/router/nvfp4_fused_router_kernel.py
index fed39c77..d57476d2 100644
--- a/dsv4/kernels/router/nvfp4_fused_router_kernel.py
+++ b/dsv4/kernels/router/nvfp4_fused_router_kernel.py
@@ -70,8 +70,12 @@ class Nvfp4FusedRouterKernel:
         self.arch = "sm_100"
 
         # Set up MMA instruction shapes
-        # These are now used inside @cute.jit context, so cute.round_up is fine
-        self.mma_inst_shape_mn = (mma_tiler_mnk[0], mma_tiler_mnk[1])
+        # All values must be CuTe/MLIR values for cute.slice_ compatibility
+        # since mma_tiler is used inside @cute.kernel with cute.slice_
+        self.mma_inst_shape_mn = (
+            cutlass.Int32(mma_tiler_mnk[0]),
+            cutlass.Int32(mma_tiler_mnk[1]),
+        )
         self.mma_inst_shape_mn_sfb = (
             self.mma_inst_shape_mn[0] // (2 if self.use_2cta_instrs else 1),
             cute.round_up(self.mma_inst_shape_mn[1], 128),
@@ -125,12 +129,12 @@ class Nvfp4FusedRouterKernel:
         self.mma_tiler = (
             self.mma_inst_shape_mn[0],
             self.mma_inst_shape_mn[1],
-            self.mma_tiler_mnk[2],
+            cutlass.Int32(self.mma_tiler_mnk[2]),
         )
         self.mma_tiler_sfb = (
             self.mma_inst_shape_mn_sfb[0],
             self.mma_inst_shape_mn_sfb[1],
-            self.mma_tiler_mnk[2],
+            cutlass.Int32(self.mma_tiler_mnk[2]),
         )
         self.cta_tile_shape_mnk = (
             self.mma_tiler[0] // cute.size(tiled_mma.thr_id.shape),
@@ -144,10 +148,10 @@ class Nvfp4FusedRouterKernel:
         )
 
         self.cluster_layout_vmnk = cute.tiled_divide(
-            cute.make_layout((*self.cluster_shape_mn, 1)),
+            cute.make_layout((cutlass.Int32(self.cluster_shape_mn[0]), cutlass.Int32(self.cluster_shape_mn[1]), cutlass.Int32(1))),
             (tiled_mma.thr_id.shape,))
         self.cluster_layout_sfb_vmnk = cute.tiled_divide(
-            cute.make_layout((*self.cluster_shape_mn, 1)),
+            cute.make_layout((cutlass.Int32(self.cluster_shape_mn[0]), cutlass.Int32(self.cluster_shape_mn[1]), cutlass.Int32(1))),
             (tiled_mma_sfb.thr_id.shape,))
 
         self.num_mcast_ctas_a = cute.size(self.cluster_layout_vmnk.shape[2])