It seems just fine to me 
in the sense that it should work, but is not really what I suggested.
The idea was that the manual addresses given to the Mikrotik interfaces should be outside the range of the addresses the DHCP of the ISP and LTE would lease, so that when/if you connect additionally another device (let’s say a laptop) directly to one of the modems/routers (to another LAN port) and it gets an IP address from DHCP there is not the possibility of an IP conflict.
You seem to have setup the addresses so that a conflict/collision in those cases is guranteed. 
(but not a problem unless in the case above)
The 8.8.4.4 is used as “canary” (or whatever you want to call it) address for the netwatch script, so there will be situations in which it goes to the blackhole route or however it is unreachable.
Not really an issue as it is the secondary DNS entry, so everything should go to 8.8.8.8 (which has - I believe an uptime of 99.999999999999…9%), but I would put a different DNS server (let’s say 1.1.1.1 or 9.9.9.9) as secondary entry.