I am looking for a solution to aggregate upto 4 LTE connections and 1 Satellite Connection.

LTE Connections 1 through to 4 are to be the main aggregated connections, the Satellite Connection will be in effect a failover.

Scenario:

We are out in the field and need 200Mb throughput speed which would be made up for the 4 LTE connections connected into a cloudcore router at the filed end and then each will be routed over a VPN Tunnel to a DataCentre Cloudcore router which will do the link bonding of all the LTE links and present a single fixed IP from that point. We would like to be able to route back over that fixed IP with port forwarding to LAN IPs, for example, we would have a machine running an FTP server on the field LAN. The Satellite will also be connected to the DataCentre Cloudcore router via VPN but traffic will only be routed in the event of all 4 LTE connections failed.

What we envision is all 5 connections in the field are tunnelled to the datacentre and then go out to the internet, were you to unplug each connection one at a time in the field the connection to internet would be sustained until all 5 have been disconnected, and when all LTE connections have been disconnected the last line (Satellite Link) would remain, but the satellite tunnel would not be used for internet traffic at all whilst any LTE connections exist.

Is this doable on MT, I have seen it work on peplink routers with speedfusion, but can not think how to visualise the config at both ends of a MT. I would very much appreciate some pointers in the right directions, as my Google-Fu is lacking searching for the correct terminilogy. Thank you in advance.

Best will be to contact one closest to you, see below link

https://mikrotik.com/consultants

Do you not think anyone on forum would be qualified to offer advice on something like this? is what I am asking that advanced?

It would be easy if not for the constantly changing parameters of the mobile networks. You mention aggregation of four LTE modems, but unless each of them has a SIM from another "real" mobile operator (different virtual operators are not enough), your SIMs from the same operator will compete for the bandwidth of the cell, and even if you really have four real mobile operators available, other users on the same cells will compete for bandwidth with you. So you may not have your 200 Mbit/s throughput all the time.

Aggregating bandwidth of multiple uplinks is relatively easy with many client devices with many connections, as each connection may use its dedicated link and statistically the load distributes evenly between them. For a single connection, you can use nth rules at per-packet level in your case where NAT is done at the other end of the bundle, but the receiving side will have tough time reassembling the stream as the packets will come in shuffled order due to different propagation times on the individual links.

So what you want is doable, but you have to describe better the expected traffic pattern, and you may still be disappointed by the practical results.