Breakthrough at the Large Hadron Collider -Leptoquarks skepticism? I have came across this recent development in the LHC:
Breakthrough at the Large Hadron Collider: https://www.youtube.com/watch?v=qR6P0aRqYf8
Leptoquarks and leptons - quarks unification:
https://en.wikipedia.org/wiki/Leptoquark

Leptoquarks (LQs) are hypothetical particles that would interact with quarks and leptons. Leptoquarks are color-triplet bosons that carry both lepton and baryon numbers. Their other quantum numbers, like spin, (fractional) electric charge and weak isospin vary among theories.

Does this mean that we are heading for a strong-EM forces unification?
Is the Electron after all coupled to the individual quarks in the nucleus via these new boson? And therefore new unifying force discovered?
 A: Let us clear up the background:
Mainstream particle physics has the standard model , a Quantum Field Theoretical model ( QFT) which not only fits the plethora of existing data , but also is mostly very successful in predicting . It is based on unifying strong , weak, and electromagnetic forces mathematically. It is supposed at very high energy that the weak and electromagnetic are unified in one force, and there is a symmetry breaking that separates the weak from the electromagnetic carriers. In the SM at the energies we have attained all the forces have their own carriers.

Does this mean that we are heading for a strong-EM forces unification?

There are the Grand Unified Theories , that try in the same way to unify weak elecgtromagnetic and strong at even higher energies, with symmetry breaking creating the seen at low energy forces.
These new  theories are proposed to solve  discrepancies with the standard model and observations, that still exist, for example,  in using the standard model to fit cosmological  data. All new theories  have to reduce to the  the standard model at low energies.
Grand unified theories are proposed for high energies, and will break down to the standard model at lower energies.

A Grand Unified Theory (GUT) is a model in particle physics in which, at high energies, the three gauge interactions of the Standard Model comprising the electromagnetic, weak, and strong forces are merged into a single force. Although this unified force has not been directly observed, the many GUT models theorize its existence. If unification of these three interactions is possible, it raises the possibility that there was a grand unification epoch in the very early universe in which these three fundamental interactions were not yet distinct.

Here is how the proton might decay in this type of theories.

In SU(5) Gut model.
The X is the carrier of all forces before symmetry breaking energies. As we have not observed a proton decay, this means there is very small probability to see the proton decay in our experiments, and estimate the X. Again, for low energies the model symmetry  has to break down to the standard model, to  be able to fit the existing data.
Here is how the Big Bang cosmological time line uses symmetry breaking:


Is the Electron after all coupled to the individual quarks in the nucleus via these new boson? And therefore new unifying force discovered?

It is always possible for the electron  to couple to quarks within the standard model, no new forces are needed. The mass of the new bosons in GUT theories is so large, that evaluating the probabilities of mediation would lead to practically zero probability. One could calculate the interaction of the electrons to the quarks with the weak force too, but the W and Z have such high mass that it is useless to do the calculation.
A: Well, the video itself is actually quite a bit more cautious than your enthusiastic endorsement/questioning. The signal at the LHCb is at 3 sigma, which means a 1 in 1000 chance of a positive evidence. Generally speaking, physicists don't get excited till they hit 5 sigma, which is 1 in 10 million chance.
The suggested explanation of a leptoquark are from GUTs, such as the Pati-Salam model or the SU(5) or SO(10) GUTs. Given that the odds have been steadily increasing it's grounds for cautious optimism but I wouldn't just celebrate just yet.
