Can't get Salesforce label values to insert

There is a customer who is currently troubleshooting a new button for a client of theirs that uses Silanis. The button initiates a new ESL document and is supposed to prepopulate some label and field values from Salesforce, but all the fields are coming in as blank. The customer has checked several times, and has this setup like all other buttons for their other documents. Here are some details: 1: Convention Field Mapping (one field example) Screen shot attached. 2: Convention Signer Label (one field example) Screen shot attached. 3: Button Setup HYPERLINK("/apex/esl__Package?ParentId=" & Id & "&Name=" & Name & "%20Subcontractor%20Agreement%20Form&EmailMessage=Please%20find%20attached%20a%20copy%20of%20your%20subcontractor%20agreement.%20%20Please%20select%20the%20Esign%20option%20and%20it%20will%20send%20your%20acceptance%20of%20the%20Subcontractor%20Agreement%20back%20to%20our%20office.&Documents=0150P000005XAgw&Signer1=" & Subcontractor_3__r.Email__c & "&Signer1FirstName=" & Subcontractor_3__r.Name & "&Signer1LastName=" & "." & "&Signer1Label=a0g0P00000EXKWH&ConventionId=a0U0P00000AfAZw&enableReminders=true&sendReminderDays=1&totalReminders=1&Insert=true&WriteBack=true&AutoPrepare=true", "Attach & Send Subcontractor Agreement Form") The convention and signer label IDs have been confirmed as being the ones the customer newly created. This particular form has about a half dozen fields, and none of them are pulling in values. Some of the fields pull directly from the Job object, and others, like the one in the example above, are mapped to pull from an object related to the job. Can you please take a look and share your inputs at the earliest?