Tom,
Will try it along with Marius' suggestion to put 44.98.63.6/8 on tunl0.
I'm not 100% sure this works on Linux, you should probably use a /32 from your allocation:
- Packets comes to your border for your subnet - Your tunl0 is in the network 44.0.0.0/8 - It has no need to forward the packet
The mere fact that the single IP is not assigned may work (i.e. kmod-ipip removes the header and places it in the netfilter chain); but if you were to change ip rules, this might cause an anomaly. Using /32 is better, I recall that being our friend's suggestion to me over the years.
- KB3VWG