some PBR rules working, others not

ERPOE 1.9.0

I have a couple of internet providers here, axia on eth0 and Lightspeed on pppoe3. eth0 is the default route, but I want certain subs to use the LS connection. Following the PBR guide, I created a routing table for the LS pppoe3 interface:

set protocols static table 1 interface-route 0.0.0.0/0 next-hop-interface pppoe3

Then I create some rules to filter certain subnets and point them to this table:

$ show configuration commands | grep modify
set firewall modify SOURCE_ROUTE rule 5 action modify
set firewall modify SOURCE_ROUTE rule 5 description 'LAN to LAN skip PBR'
set firewall modify SOURCE_ROUTE rule 5 destination group network-group LOCAL
set firewall modify SOURCE_ROUTE rule 5 modify table main
set firewall modify SOURCE_ROUTE rule 10 action modify
set firewall modify SOURCE_ROUTE rule 10 description 'PBR test_router to LS pppoe3'
set firewall modify SOURCE_ROUTE rule 10 modify table 1
set firewall modify SOURCE_ROUTE rule 10 source address 10.2.31.45
set firewall modify SOURCE_ROUTE rule 15 action modify
set firewall modify SOURCE_ROUTE rule 15 description 'traffic from LP_WISP to Lightspeed'
set firewall modify SOURCE_ROUTE rule 15 modify table 1
set firewall modify SOURCE_ROUTE rule 15 source address 10.4.23.0/24
set firewall modify SOURCE_ROUTE rule 16 action modify
set firewall modify SOURCE_ROUTE rule 16 description 'traffic from LP_WISP_30 to Lightspeed'
set firewall modify SOURCE_ROUTE rule 16 modify table 1
set firewall modify SOURCE_ROUTE rule 16 source address 10.4.24.0/24
set firewall modify SOURCE_ROUTE rule 20 action modify
set firewall modify SOURCE_ROUTE rule 20 description 'traffic from switch0.430 to Axia'
set firewall modify SOURCE_ROUTE rule 20 modify table 2
set firewall modify SOURCE_ROUTE rule 20 source address x.x.x.65/27
set interfaces ethernet eth4 firewall in modify SOURCE_ROUTE
set interfaces switch switch0 vif 430 firewall in modify SOURCE_ROUTE

I can see some traffic from 10.2.31.45 on the pppoe3 interface, so I know that rule 10 is doing something. However I can see lots of traffic from 10.4.23.0/23 on eth0, and none of it on pppoe3, so it appears that rules 15 and 16 are not working.

How can I dig into this deeper and find out why traffic from 10.4.23.0/23 is not hitting rules 15 and 16?