You accepted his response to you, and shipped your unit, after he said "as soon as he could" for the tirn around time. The result was: he did not provide you with a more specific time frame for the repairs AND you had only your imagination, to guess when your gear would be returned.
IF you had gently challenged his wishy-washy response right away, you could have accomplished a few things. By "challenging" I mean saying something like, "Robert, I hear you saying you are busy, and it must be great to get all of this positive feedback on your hard work. As a valued customer, before I send my unit back to you, can we look at the calendar and agree, more specifically, on when I will be able to enjoy it again?"
With his response, you could have either said "yes," "no," or negotiated a compromise that you thought was fair. When you accepted his vague time frame, you gave your consent to his assigning a lower priority to your repair than you imagined, at that time.
So, today, things have continued to go south, in this matter, and who knows if, when, or in what condition your unit will be returned! If it was me, I would weigh the cost and inconvenience of physically going to get the unit and then paying for its repair, with the anticipated sonic benefits of "everything working." Won't you feel better, after this mess is finally resolved, one way or another? Make it happen, and move on.
Moral of the story: when you accept "wishy-washy" from someone, in many cases it can become an uphill battle, if not an impossible task, to turn this communication into an exchange with clear, mutually agreed-on terms between two adults with sincere intentions.
It happens to all of us; "live and learn."