after a week of waiting, we've got some more info. his body IS making RBC, lots of them, and his spleen tissues are healthy and full of RBC. but his anemia is progressively getting worse, and his count as of today was super-low. 1.88 is what they told me, so we're putting him on b12 and folates tomorrow, as well as the iron supplements he's on. since the ultrasound indicates no internal bleeding and his heart appears to be functioning properly and his bone marrow is producing what it should be and his organ function is OK, we're looking at two possibilities:
he might have a tick-related disease, such as babesia, that hasn't shown up in a positive test yet, so we're probably going to start him on treatment for one of those just in case (though the vet says this is "controversial" and he's going to run another test for all the tick diseases again, just in case)
he might have an auto-immune disorder. i'm supposed to go in tomorrow to talk to the vet at lunch about the potential for immunosuppresants ... i know nothing about this, but i know others here have dealt with IMHA and AIHA, so if anyone has any stories, good or bad, to share, i'm now looking for more information on these conditions.

he sounds like he is in excellent care. Sending healing wishes to your sweet boy!
