The characteristic question for maqbūlāt is: Who supplied the claim, and why is that person trusted? For maẓnūnāt it is: What indications make this claim more probable than its alternative?
Accepted report: “An experienced builder advises additional structural support.” The source’s expertise carries the initial weight.
Probable indication: “New cracks and visible movement suggest that additional support may be needed.” Observations support a tentative judgment.
The two can jointly inform a decision, while remaining different kinds of premise.