I think this would be the “non-compassionate” approach of claiming that their meditative attainments were not exactly how the Buddha described jhana, so it has nothing to do with jhana.
However, the Buddha himself speaks of meditative achievements of his teachers in MN26. In DN1 he talks about how some develop wrong views due their meditative attainments.
For example:
“In the first case, bhikkhus, some recluse or a brahmin, by means of ardour, endeavour, application, diligence, and right reflection, attains to such a degree of mental concentration that with his mind thus concentrated, [purified, clarified, unblemished, devoid of corruptions], he recollects his numerous past lives: that is, (he recollects) one birth, two, three, four, or five births; ten, twenty, thirty, forty, or fifty births; a hundred, a thousand, or a hundred thousand births; many hundreds of births, many thousands of births, many hundreds of thousands of births. (He recalls:) ‘Then I had such a name, belonged to such a clan, had such an appearance; such was my food, such my experience of pleasure and pain, such my span of life. Passing away thence, I re-arose there. There too I had such a name, belonged to such a clan, had such an appearance; such was my food, such my experience of pleasure and pain, such my span of life. Passing away thence, I re-arose here.’ Thus he recollects his numerous past lives in their modes and their details.
“He speaks thus: ‘The self and the world are eternal, barren, steadfast as a mountain peak, standing firm like a pillar. And though these beings roam and wander (through the round of existence), pass away and re-arise, yet the self and the world remain the same just like eternity itself. What is the reason? Because I, by means of ardour, endeavour, application, diligence, and right reflection, attain to such a degree of mental concentration that with my mind thus concentrated, I recollect my numerous past lives in their modes and their details. For this reason I know this: the self and the world are eternal, barren, steadfast as a mountain peak, standing firm like a pillar. And though these beings roam and wander (through the round of existence), pass away and re-arise, yet the self and the world remain the same just like eternity itself.’
Their attainments seemed to have much the same effect as the jhanas described in MN36:
“When my concentrated mind was thus purified, bright, unblemished, rid of imperfection, malleable, wieldy, steady, and attained to imperturbability, I directed it to knowledge of the recollection of past lives. I recollected my manifold past lives, that is, one birth, two births…
Their problem seems to be that they did not have the correct wisdom/insight, not that they could not develop concentration.