@spec19 The letter of determination from anmac<b class="Bold"> is</b> your determining factor on how much points to claim. Which is why you only apply for an EOI after an assessment is made by anmac. If an EOI is lodged prior to an assessment outcome, this might and actually confirmed by many as visa refusal.
One cannot claim points for an experience <b class="Bold">not</b> assessed by ANMAC or any other assessing body for that matter. If the professional experience is not written in the LOD, then it can't be claimed. A lot of people actually miss this part and not read the LOD resulting in overclaiming of points which is again grounds for refusal.
In short, any professional experiences of any profession if not assessed by their assessing authorities to obtain a valid skills assessment, should not be claimed.
You can however email or talk to ANMAC and explain why you are not able to provide proof of those employments. If I'm not mistaken, to actually verify that you have worked in those countries, ANMAC will require proof such as your COGS, a reference letter, maybe a statutory declaration. If ANMAC decides that your proof were enough for an experience, then that shall reflect in your LOD. At this point, try and communicate with ANMAC if you really want to claim those experience.