lazy loading of my module fails program loading

I’m trying to load a module dynamically (depends on the number of algorithms in the backend application). The angular app compiles but doesn’t load once I add the routes dynamically.
If I add them statically (hardcoded) they load fine.

Thanks in advance!
Relevant code snippets below:

lab-routing.module.ts:

export const MLRoutes: Routes = [];
export const NormRoutes: Routes = [];
export const LAB_ROUTES: Routes = [{
  path: '',
  component: LabComponent,
  children: [
    {
      path: 'Dashboard',
      component: LabDashboardComponent,
    },
    {
      path: '',
      redirectTo: 'Dashboard',
      pathMatch: 'full',
    },
    {
      path: '**',
      component: NotFoundComponent,
    },
  ],
}];

lab-menu.ts:

export function insert_ml(algo: string): void {
  ML_ITEMS.push({
    title: algo,
    icon: 'keypad-outline',
    children: [
      {
        title: 'Datasets',
        icon: 'activity-outline',
        link: `/lab/${algo}/dataset`,
      },
      {
        title: 'Results',
        icon: 'bar-chart',
        link: `/lab/${algo}/results`,
      },
    ],
  });

  MLRoutes.push({
    path: algo,
    loadChildren: () => import('./ml-algo/ml-algo.module').then(m => m.MLAlgoModule),
  });
}

lab-dashboard.component.ts:

public refresh() {
    this.http.get('http://localhost:5000/refresh').subscribe(
      data => {
        if (data['success']) {
          data['ml_algos'].forEach(algo => insert_ml(algo));
          data['norm_algos'] .forEach(algo => insert_norm(algo));
          build_menu();
        }
      },
    );
  }

ml-algo-routing.module.ts:

const routes: Routes = [{
  path: '',
  component: MLAlgoComponent,
  children: [
    {
      path: 'dataset',
      component: MLDatasetComponent,
    },
    {
      path: 'results',
      component: MLGraphsComponent,
    },
  ],
}];