Sorry for the late reply I’m not super active on forums if you ever need me I respond to emails with in minutes/hours at most times unless it’s sleep time.
I won’t mix different lab products or carrier oils personally. I would just use a draw needle for each and load all in one syringe then switch to a 23-25 gauge needle.
out of all the years I haven’t seen moldy gear that’s very unusual.
If I need to replace something no problem at all.
Mixing different compounds from different sources can change the ratios of solvents used to keep gear in suspension.
I wouldn’t even try to bring that gear back into suspension by heating it id toss it out, it looks milky not even so much as if it just crashed.