What is a check valuation?

I've been disputing a valuation on one of properties and the broker back to me with this.

Quote:

"We have had Propell review their valuation & assess with additional comparable sales They have completed a thorough review however have confirmed that an increase in value is not supported We have therefore ordered a check valuation and will advise upon it's receipt - ensure customers aware of new inspection"

What does this mean? It sounds like they are saying, they are not moving from their valuation, but then what is this check valuation about?

(Unfortunately the broker's assistance does not know what it means either and the broker is not available).

What is a check valuation?