Cannot get TFTP to work across Management Interface

I'm configuring a 4300 ISR that I want to update but I can't get TFTP working across the management interface/VRF.

I've seen multiple posts about setting the TFTP source interface to the management interface but that hasn't done anything for me. The TFTP connection fails with:

%Error opening tftp://172.16.0.79/isr4300-universalk9.03.16.07.S.155-3.S7-ext.SPA (No such file or directory) 

I've used this TFTP server for multiple updates this week so I know it's not a problem with the TFTP server/firewall. Is there anything else I can try besides removing the management port from it's VRF?

Here's the config, this is an out of the box 4331 ISR.

vrf definition Mgmt-intf ! address-family ipv4 exit-address-family ! address-family ipv6 exit-address-family interface GigabitEthernet0 vrf forwarding Mgmt-intf ip address 172.16.0.167 255.255.255.0 negotiation auto ip tftp source-interface GigabitEthernet0 ip route vrf Mgmt-intf 0.0.0.0 0.0.0.0 172.16.0.1 

Here's the Mgmt-intf routing table

Routing Table: Mgmt-intf Gateway of last resort is 172.16.0.1 to network 0.0.0.0 S* 0.0.0.0/0 [1/0] via 172.16.0.1 172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks C 172.16.0.0/24 is directly connected, GigabitEthernet0 L 172.16.0.167/32 is directly connected, GigabitEthernet0