Can a Taxpayer who's both self-employed and a W2 employee get credit for the EMPLOYER part of his self-employment FICA tax, if his W2 employer already paid the max FICA?

If Taxpayer A is both an independent contractor (with self-employed business income) and an employee (with W2 wages, paid by a Third Party Employer), can Taxpayer A:

• get credit for the amount he paid for the employer portion of his self-employment social security tax, if 
• his Third Party Employer already fully paid the employer portion of the social security tax on Taxpayer A’s maximum taxable earnings ($128,400 in 2018) from Taxpayer A’s W2 job? 

I know Taxpayer A can get credit for the employee portion of any social security tax ‘overpaid’ across the two jobs (independent contractor work and W2 job) combined.

Please provide the source and/or authority for your answer, if possible.

Thank you!