Here is the config from one of the 2930s.
They are all configured the same aside from the IPs and 1 of the routing statements.
Would entering a udp broadcast statment on VLAN 20 for ports 67 & 68 pointing to the DHCP server work or a no udp broadcast for dhcp pointing back to the VLAN 20 DHCP server, do the trick?
Running Configuration
; JL258A Configuration Editor; Created on release #WC.16.05.0007
; Ver #12:08.1d.9b.3f.bf.bb.ef.7c.59.fc.6b.fb.9f.fc.ff.ff.37.ef:ba
hostname "Aruba-2930F-8G-LINC"
module 1 type jl258a
no dhcp-relay
time daylight-time-rule continental-us-and-canada
time timezone -6
ip route 0.0.0.0 0.0.0.0 10.20.0.2
ip route 10.2.0.0 255.255.0.0 10.20.0.2
ip route 10.2.15.10 255.255.255.255 blackhole
ip route 10.3.0.0 255.255.0.0 10.20.0.3
ip route 10.3.1.91 255.255.255.255 blackhole
ip route 10.4.0.0 255.255.0.0 10.20.0.4
ip route 10.5.0.0 255.255.0.0 10.20.0.5
ip route 10.6.0.0 255.255.0.0 10.20.0.6
ip route 10.9.0.0 255.255.0.0 10.20.0.9
ip route 10.10.0.0 255.255.0.0 10.20.0.1
ip routing
interface 1
no power-over-ethernet
exit
interface 2
no power-over-ethernet
exit
interface 3
no power-over-ethernet
exit
interface 4
no power-over-ethernet
exit
interface 5
no power-over-ethernet
exit
interface 6
no power-over-ethernet
exit
interface 7
no power-over-ethernet
exit
interface 8
no power-over-ethernet
exit
snmp-server community "public" unrestricted
snmp-server location "Lincoln"
vlan 1
name "DEFAULT_ELAN"
no untagged 2-10
untagged 1
ip address 10.20.0.7 255.255.255.0
exit
vlan 20
name "Linc-LAN"
untagged 2-10
tagged 1
ip address 10.7.1.1 255.255.0.0
ip helper-address 10.7.1.2
exit