MA source income is not a condition for residency; it only controls whether or not MA can tax the income of a non-resident. If an MA non-resident (any MA non-resident) has MA source income, MA can impose a tax on that income.
I should add that it appears the only connection the trust at issue here has with MA is that you, as trustee, are an MA resident and, according to the instructions (link in the answer), that is not sufficient to confer MA residency on the trust.
