Unity Shader issue

Ok so I’m creating a grid based map mesh and coloring the vertexes based on what terrain each tile will be; then a texture array is used to map textures to those colors. (As i understand the process) so the issue is the small quad area inbetween 4 tiles. I’m attempting to blend the 4 surrounding colors, the splat map should be doing a channel on R,G,B,A and each of those values carries a value of 1 for the vertext/splat mapping.

I wind up with this:https://imgur.com/a/ybS7ZvT It displays 4 textures from the texture array, but the one spot I try to blend 4 colors refuses to show anything but a single texture.

Here’s the shader code I’ve worked up to this point. Am I just missing something simple or is this a more complex problem?

Shader "Custom/TileShader" {
	Properties {
		_Color ("Color", Color) = (1,1,1,1)
		_MainTex ("Terrain Texture Array", 2DArray) = "white" {}
		_Glossiness ("Smoothness", Range(0,1)) = 0.5
		_Metallic ("Metallic", Range(0,1)) = 0.0
	}
	SubShader {
		Tags { "RenderType"="Opaque" }
		LOD 200

		CGPROGRAM
		// Physically based Standard lighting model, and enable shadows on all light types
		#pragma surface surf Standard fullforwardshadows vertex:vert

		// Use shader model 3.5 target, to get nicer looking lighting
		#pragma target 3.5

		UNITY_DECLARE_TEX2DARRAY(_MainTex);

		struct Input {
			float4 color : COLOR;
			float3 worldPos;
			float4 terrain;
		};

		half _Glossiness;
		half _Metallic;
		fixed4 _Color;

		// Add instancing support for this shader. You need to check 'Enable Instancing' on materials that use the shader.
		// See https://docs.unity3d.com/Manual/GPUInstancing.html for more information about instancing.
		// #pragma instancing_options assumeuniformscaling
		UNITY_INSTANCING_BUFFER_START(Props)
			// put more per-instance properties here
		UNITY_INSTANCING_BUFFER_END(Props)

		void vert (inout appdata_full v, out Input data) {
			UNITY_INITIALIZE_OUTPUT(Input, data);
			data.terrain = v.texcoord2;
		}

		float4 GetTerrainColor (Input IN, int index) {
			float3 uvw = float3(IN.worldPos.xz * 0.02, IN.terrain[index]);
			float4 c = UNITY_SAMPLE_TEX2DARRAY(_MainTex, uvw);
			return c * IN.color[index];
		}

		void surf (Input IN, inout SurfaceOutputStandard o) {
			fixed4 c = 
				GetTerrainColor(IN, 0) +
				GetTerrainColor(IN, 1) +
				GetTerrainColor(IN, 2) +
				GetTerrainColor(IN, 3);
			o.Albedo = c.rgba;
			// Metallic and smoothness come from slider variables
			o.Metallic = _Metallic;
			o.Smoothness = _Glossiness;
			o.Alpha = c.a;
		}
		ENDCG
	}
	FallBack "Diffuse"
}