I have located the problem by following the instructions on the RMA Victron page. I know this issue not covered under warranty.
I didn’t have my glasses on and reversed the polarity when connecting the battery to the + - poles on the 100/30 MPPT controller.
In the Victron MPPT controller, can the non-replaceable fuse be repaired?
This is not intended, as the interior is moulded. If you want to try it …
More interesting is the ‘Enlish’ type of fuse similar to a D02 fuse with solder connections
Replacement is only possible with a great deal of thermal effort due to the amount of solder and thermal dissipation …
… and whether the Mppt will work again afterwards is questionable
I was curious to see what and where the fuse was and what it looked like. I was about to pry the unit open and thought better as I wouldn’t have the parts.
I will see if the cover can be removed without the surgery and then call the local Victron solar dealer and see what they say about a possible repair.
I appreciate your reply. The answer is clear in that even with a replaced fuse there can still be further complications.
I bought a new unit to replace the damaged one and am willing to invest a little money into the repair to find out the answer. I’ll post my results.
you still have several videos available where the ‘cover’ is also removed … this rarely works well … the chokes or the capacitors break quickly … but as the saying goes … ‘Trial makes perfect’ … probably translated wrong 
Was it battery only connected at that time?
If it was the only thing then it won’t have blown a fuse or done any damage.
Yes. Only the battery. I had one pole connected and as I touched the other the spark looked like an arc as opposed to a spark.
What I learned is that a fuse between the battery and MPPT controller is necessary to prevent this type of human error. Being that I remove the 100 Amp hour LiFePo4 battery occasionally when there is no sun to charge it with my Victron battery charger elsewhere.
Edited to add: I do have a fuse from the positive terminal on the battery. It didn’t blow but it is a 125A fuse. Probably to high to prevent this kind of short. I should have done this prior, however I just asked Google: what amperage of fuse should be placed between an MPPT controller and Lifepo4 battery?
The fuse or breaker you should place between an MPPT controller and a lithium iron phosphate (LiFePO4) battery should be 1.25 times the maximum output current of the charge controller. For example, if the charge controller’s maximum current rating is 30 amps, you should use a 40-amp fuse or breaker.
I have a Victron Smart Controller 100/30.
I concluded there is an issue with the non replaceable fuse when the battery failed to charge. Following the RMA instructions:
Set a Multimeter to diode position.
Connect the multimeter positive wire (red) to the PV positive terminal.
Connect the multimeter negative (black) wire to the Battery positive terminal.
What value does the Multimeter indicate?
The reading is above .08V
And then:
Power the solar charger using a bench power supply set to 12V with a current limit of 0.5A, connected to the battery terminals, or a 12V battery with a 0.5A fuse in the positive supply.
Are any LED(s) blinking or on, are all LEDs briefly on and then off again or is the solar charger drawing a small current (40 - 70mA)?
There were no lights.
After some armchair research I decided to go for it.
Congratulations 
with the small Mppts the capacitors are apparently lying flat and therefore the potting compound doesn’t stick to the cover as well …
Thank You! I was inspired.
It was the luck of the draw. Most of the potting compound was on the casing.
Mabey it was a Friday night at 5 o’clock when the assembler poured it? Who knows.
