How to end a Rex search with mutiple characters or a string sub as } }?

Sample data:

{ "active" : "Y“, “locationID" : 75942068, "existsFlag" : true, "manuallyUnarchived" : false, "pendingReminder" : false, "headerOperationType" : "TRN“, “headerCreationDateString" : "2019111307255700“, “headerCreationDateEpoch" : "1573651557“, “jobs" : [ { "jobNumber" : "RWERQ70“, “jobVendorNum" : "ACME“, “jobAcknowledgementDateString" : "2019-11-08:10:42“, “jobAcknowledgementDateEpoch" : "1573231320“, “jobPodDateString" : "2019-11-13:05:44“, “jobPodDateEpoch" : "1573645440“, “jobShipDateString" : "2019-11-08:11:20“, “jobShipDateEpoch" : "1573233600“, “jobStatusCode" : "DELIVERED“, “jobPartNumbers" : [ { "skuMfgNbr" : "AS3452“, “quantity" : 1 } ], "partShippedDescription" : "SHP142SVC" } ], "comments" : [ { "commentType" : "PRB“, “commentDateEpoch" : "1573192800000“, “arrivalWindowStart" : 1573477200000, "arrivalWindowEnd" : 1573858740000, "avsUsed" : "N“, “laborStatusCode" : "ETA Provided“, “partStatusCode" : "Delivered“, “owner" : { "businessUnit" : 0, "certifiedFlag" : false, "techId" : 0 }, "environment" : "None“, “subEnvironment" : "Other“, “shortComment" : "TechDirection : Other“, “dispatchCreationDateEpoch" : "1573230503“, “serviceAttributes" : { "ServiceType" : "FixerUpper“, “OutofHours" : "N“, “OutofWarranty" : "N“, “ServiceHours" : "10x1“, “ADOverrideRequest" : "N" } }, "address" : { "address" : "1 Main St“, “address1" : "1 Main St“, “city" : "Nowhere“, “country" : "US“, “postalCode" : "12345" }

I need a field containing all the text from "activity" all the way to } }, (the double curly brackets separated by a space and followed by a comma, located right before "address" field. I could do this with if a single terminator character ( } ), as in the example below, but that would only give me half of the data needed. I need a Rex that gives me all the data betwen "activity" and the } } (the two curly brackets). The two curly brackets indicate the end of the main field).

This works: | rex field=_raw "\"activity\"(?&ltACTIVITY_FIELDS&gt[^\}]+)"

This is what I need, but it does not work: | rex field=_raw "\"activity\"(?&ltACTIVITY_FIELDS&gt[^\}\s\}]+)"

Thanks for any assistance provided.