As someone who had a painfully slow courtship from DH of now 33 years :) in a very similar sounding, scientific, high profile work environment for both of us. I think he is SO into you. He really, really is.
Can't give too much details as would out myself, but yes, the guarding your back, the sending the team to help you in an uncomfortable situation, the noticing things, the wonderful written notes and phone chats ( pre email/text for us, although we were at the forefront of internet usage, it had to be kept for work only), the general showing how he feels about you, even though inarticulate and shy trying to say how he feels.
Mine summoned up his courage to actually declare himself (interestingly, it took a change of department for me, with an office move to another site ! I had a similar " don't go" declaration) after about a year of all this. A month or so of a bit more intimate stuff ( meals, drinks, outings to stuff) An office party followed (NYE) where he made it clear ( with my prior agreement!) we were An Item. We went home together that night :)
A year and a bit later, we were married :)