Okay, those are definitely heat signs. Huang Qi, which is part of Bu Yang Huan Wu Tang (his formula for hemangiosarcoma) is heating, so I guess that's why. You could try a small amount of Long Dan Xie Gan Tang - a spoon or two twice daily to counterbalance that. It should be a third or a quarter of the BYHWT, so we don't damage his Qi, which we assessed as deficient. That's how BYHWT works - it tonifies Qi to move Blood. So just give enough to take the edge off.
The other possibility is his orifices are obscured by Phlegm. In which case adding some Shi Chang Pu to his formula may help. I'll let your intuition mull over which is the better choice for Beau.