Using Rendertexture on Android Native JAR

Hello, I'm trying to render an image using GLES in an Android Java library. When I try to clear the color buffer or attempt to draw to the binded rendertexture, I get a glerror 1286. From what I researched, this error is a result of an invalid framebuffer being used. Are unity rendertextures the same as a framebuffer? How should I use a GL_TEXTURE_EXTERNAL_OES texture in Unity?

Here's what I have so far:

Java:

         public void drawFrame(SurfaceTexture st, boolean invert, int renderTexture) {
             //bind to unity rendertexture
             GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, renderTexture);
             checkGlError("glBindFramebuffer");
             GLES20.glViewport(0,0, 512, 512);
             checkGlError("glViewport");
             GLES20.glDisable(GLES20.GL_DEPTH_TEST);
             checkGlError("onDrawFrame start");
             st.getTransformMatrix(mSTMatrix);
             if (invert) {
                 mSTMatrix[5] = -mSTMatrix[5];
                 mSTMatrix[13] = 1.0f - mSTMatrix[13];
             }
 
             GLES20.glUseProgram(mProgram);
             checkGlError("glUseProgram");
 
             //binding the gl texture oes from an android surfacetexture
             GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
             GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, mTextureID);
             mTriangleVertices.position(TRIANGLE_VERTICES_DATA_POS_OFFSET);
             GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false,
                     TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
             checkGlError("glVertexAttribPointer maPosition");
             GLES20.glEnableVertexAttribArray(maPositionHandle);
             checkGlError("glEnableVertexAttribArray maPositionHandle");
 
             mTriangleVertices.position(TRIANGLE_VERTICES_DATA_UV_OFFSET);
             GLES20.glVertexAttribPointer(maTextureHandle, 2, GLES20.GL_FLOAT, false,
                     TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
             checkGlError("glVertexAttribPointer maTextureHandle");
             GLES20.glEnableVertexAttribArray(maTextureHandle);
             checkGlError("glEnableVertexAttribArray maTextureHandle");
 
             Matrix.setIdentityM(mMVPMatrix, 0);
             GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mMVPMatrix, 0);
             GLES20.glUniformMatrix4fv(muSTMatrixHandle, 1, false, mSTMatrix, 0);
 
             //draw the surfacetexture to the rendertexture returning glError 1286
             GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
             checkGlError("glDrawArrays");
 
             GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, 0);
             GLES20.glEnable(GLES20.GL_DEPTH_TEST);
             //unbind rendertexture
             GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);
         }

Unity C#:

         if (!textureTarget)
         {
             textureTarget = new RenderTexture(512, 512, 16, RenderTextureFormat.ARGB32);
             textureTarget.filterMode = FilterMode.Point;
             textureTarget.wrapMode = TextureWrapMode.Clamp;
             textureTarget.Create();
             if (material) material.sharedMaterial.mainTexture = textureTarget;
         }
         //update surfacetexture
         exoPlayer.Call("updateTexture");
         //draw to rendertexture
         exoPlayer.Call("drawFrame", (int)textureTarget.GetNativeTexturePtr());