Can a redux-form accept multiple values from a react-select component?

Yes, it's possible. You have to create a custom component, that will wrap react-select and will use the props, passed down by redux-form <Field component={YourCustomComponent} />.

1. Here's is described how to create such a custom component in the official redux-form documentation.
2. Here, you will find such already implemented components, these wrap react-select and connects them with redux-form: ReactJS: How to wrap react-select in redux-form field ?
3. In order to handle multi values, please refer to this SO answer.

Basically, the code example from resource 3. (credits to the author) should be enough for integrating react-select + redux-form + handling multi values:

SelectInput.js

import React from 'react';
import Select from 'react-select';
import 'react-select/dist/react-select.css';

export default (props) => (
  <Select
    {...props}
    value={props.input.value}
    onChange={(value) => props.input.onChange(value)}
    onBlur={() => props.input.onBlur(props.input.value)}
    options={props.options}
  />
);

MyAwesomeComponent.js

import React, {PureComponent} from 'react';
import SelectInput from './SelectInput.js';

class MyAwesomeComponent extends PureComponent {
  render() {
    const options = [
      {'label': 'Germany', 'value': 'DE'},
      {'label': 'Russian Federation', 'value': 'RU'},
      {'label': 'United States', 'value': 'US'}
    ];
  return (
    <Field
      name='countries'
      options={options}
      component={SelectInput}
      multi
    />
  )
};