If you're unsure whether the clause was professionally drafted, you will probably decide:

• To note this, so you can come back later, and look again at whether the clause was professionally drafted, if it might then make a difference.
• To give the supplier the benefit of the doubt for now, and see if their claim would be a good one, if their clause is effective.
• To run the question past us, if it looks as if this supplier might have a good claim.