If anyone is curious, the logs show that __ZULU_URL= is being set on both calls at the incoming route level. It then passes on via UserEvent:zulu-call correctly for the first queue, but is not passed for the second or the new queue I setup to test with either.
On that second queue, the logs show an additional line which appears to be overwriting the __ZULU_URL from the incoming route with the one which is blank from the queue.
Executing [1201@ext-queues:40] Set("SIP/myprovider-00000091", "__ZULU_URL=") in new stack
in the extensions_additional.conf file: (117 good, 1201 bad, line 40 of each config being the __ZULU_URL)
exten =117,n,Set(__ZULU_TYPE=)
exten =117,n,Set(__ZULU_URL=)
...
exten =1201,n,Set(__ZULU_TYPE=)
exten =1201,n,Set(__ZULU_URL=)
The fuller logs:
[2017-05-19 09:39:20] VERBOSE[16844] loader.c: -- Reloading module 'res_config_curl.so' (Realtime Curl configuration)
[2017-05-19 09:39:35] VERBOSE[16993][C-00000035] pbx.c: -- Executing [18885555555@from-trunk:21] Set("SIP/myprovider-0000008d", "__ZULU_TYPE=url") in new stack
[2017-05-19 09:39:35] VERBOSE[16993][C-00000035] pbx.c: -- Executing [18885555555@from-trunk:22] Set("SIP/myprovider-0000008d", "__ZULU_URL=http://myurl.com/incoming.php?a=search&callerid_num=+15555555555&callerid_name=RG-AD-MYLAST MYFIRST&source=RG-AD&context=from-trunk") in new stack
[2017-05-19 09:39:36] VERBOSE[17008][C-00000035] pbx.c: -- Executing [s@macro-dial-one:51] GotoIf("Local/14@from-queue-00000054;2", "1?zulunourl") in new stack
[2017-05-19 09:39:36] VERBOSE[17008][C-00000035] pbx.c: -- Executing [s@macro-dial-one:55] UserEvent("Local/14@from-queue-00000054;2", "zulu-call,eventtype:calling,extension:14,type:url,url:aHR0cDovL25v***jcy5jb20vaW5jb21pbmcucGhwP2E9c2VhcmNoJmNhbGxlcmlkX251bT0rMTYw***zMDIyMTMmY2FsbGVyaWRfbmFtZT1SRy1BRC1PSFIgTUlDSEVBTCZzb3VyY2U9UkctQUQmY29udGV4dD1mcm****RydW5r,cnam:RG-AD-MYLAST MYFIRST,cnum:+15555555555,lid:1495201175.305") in new stack
[2017-05-19 09:39:36] VERBOSE[17006][C-00000035] pbx.c: -- Executing [s@macro-dial-one:51] GotoIf("Local/13@from-queue-00000052;2", "1?zulunourl") in new stack
[2017-05-19 09:39:36] VERBOSE[17006][C-00000035] pbx.c: -- Executing [s@macro-dial-one:55] UserEvent("Local/13@from-queue-00000052;2", "zulu-call,eventtype:calling,extension:13,type:url,url:aHR0cDovL25v***jcy5jb20vaW5jb21pbmcucGhwP2E9c2VhcmNoJmNhbGxlcmlkX251bT0rMTYw***zMDIyMTMmY2FsbGVyaWRfbmFtZT1SRy1BRC1PSFIgTUlDSEVBTCZzb3VyY2U9UkctQUQmY29udGV4dD1mcm****RydW5r,cnam:RG-AD-MYLAST MYFIRST,cnum:+15555555555,lid:1495201175.305") in new stack
[2017-05-19 09:39:36] VERBOSE[17007][C-00000035] pbx.c: -- Executing [s@macro-dial-one:51] GotoIf("Local/17@from-queue-00000053;2", "1?zulunourl") in new stack
[2017-05-19 09:39:36] VERBOSE[17007][C-00000035] pbx.c: -- Executing [s@macro-dial-one:55] UserEvent("Local/17@from-queue-00000053;2", "zulu-call,eventtype:calling,extension:17,type:url,url:aHR0cDovL25v***jcy5jb20vaW5jb21pbmcucGhwP2E9c2VhcmNoJmNhbGxlcmlkX251bT0rMTYw***zMDIyMTMmY2FsbGVyaWRfbmFtZT1SRy1BRC1PSFIgTUlDSEVBTCZzb3VyY2U9UkctQUQmY29udGV4dD1mcm****RydW5r,cnam:RG-AD-MYLAST MYFIRST,cnum:+15555555555,lid:1495201175.305") in new stack
2017-05-19 09:46:57] VERBOSE[18766] loader.c: -- Reloading module 'res_config_curl.so' (Realtime Curl configuration)
[2017-05-19 09:47:19] VERBOSE[18982][C-00000036] pbx.c: -- Executing [18885555555@from-trunk:21] Set("SIP/myprovider-00000091", "__ZULU_TYPE=url") in new stack
[2017-05-19 09:47:19] VERBOSE[18982][C-00000036] pbx.c: -- Executing [18885555555@from-trunk:22] Set("SIP/myprovider-00000091", "__ZULU_URL=http://myurl.com/incoming.php?a=search&callerid_num=+15555555555&callerid_name=RG-AD-MYLAST MYFIRST&source=RG-AD&context=from-trunk") in new stack
**[2017-05-19 09:47:27] VERBOSE[18982][C-00000036] pbx.c: -- Executing [1201@ext-queues:40] Set("SIP/myprovider-00000091", "__ZULU_URL=") in new stack**
[2017-05-19 09:47:27] VERBOSE[19004][C-00000036] pbx.c: -- Executing [s@macro-dial-one:51] GotoIf("Local/13@from-queue-00000056;2", "1?zulunourl") in new stack
[2017-05-19 09:47:27] VERBOSE[19004][C-00000036] pbx.c: -- Executing [s@macro-dial-one:57] UserEvent("Local/13@from-queue-00000056;2", "zulu-call,eventtype:calling,extension:13,type:,url:,cnam:RG-AD-MYLAST MYFIRST,cnum:+15555555555,lid:1495201639.315") in new stack
[2017-05-19 09:47:27] VERBOSE[19003][C-00000036] pbx.c: -- Executing [s@macro-dial-one:51] GotoIf("Local/30@from-queue-00000055;2", "1?zulunourl") in new stack
[2017-05-19 09:47:27] VERBOSE[19003][C-00000036] pbx.c: -- Executing [s@macro-dial-one:57] UserEvent("Local/30@from-queue-00000055;2", "zulu-call,eventtype:calling,extension:30,type:,url:,cnam:RG-AD-MYLAST MYFIRST,cnum:+15555555555,lid:1495201639.315") in new stack
[2017-05-19 09:47:27] VERBOSE[19006][C-00000036] pbx.c: -- Executing [s@macro-dial-one:51] GotoIf("Local/14@from-queue-00000058;2", "1?zulunourl") in new stack
[2017-05-19 09:47:27] VERBOSE[19006][C-00000036] pbx.c: -- Executing [s@macro-dial-one:57] UserEvent("Local/14@from-queue-00000058;2", "zulu-call,eventtype:calling,extension:14,type:,url:,cnam:RG-AD-MYLAST MYFIRST,cnum:+15555555555,lid:1495201639.315") in new stack
[2017-05-19 09:47:27] VERBOSE[19005][C-00000036] pbx.c: -- Executing [s@macro-dial-one:51] GotoIf("Local/17@from-queue-00000057;2", "1?zulunourl") in new stack
[2017-05-19 09:47:27] VERBOSE[19005][C-00000036] pbx.c: -- Executing [s@macro-dial-one:57] UserEvent("Local/17@from-queue-00000057;2", "zulu-call,eventtype:calling,extension:17,type:,url:,cnam:RG-AD-MYLAST MYFIRST,cnum:+15555555555,lid:1495201639.315") in new stack