(2) Employer medical assistance contributions, credits, interest, and penalties associated with an employer's liability under M.G.L. c. 149, § 189 shall be credited or charged to the Commonwealth Care Trust Fund only and shall not be credited or charged to that employer's unemployment insurance account or the solvency account established by M.G.L. c. 151A, § 14. Likewise, employer payments, credits, contributions, interest, and penalties associated with unemployment insurance contributions shall be credited or charged to the employer's unemployment insurance account or solvency account, whichever is applicable.